Trac Bar?

[jojobafanzi]

Has anyone installed a rear Trac Bar on a Class B? I'm making repairs on my rear suspension. 2017 Roadtrek Versatile 170 on Chevy Express platform. Thanks in advance. Joe

[booster]

Originally Posted by jojobafanzi

Has anyone installed a rear Trac Bar on a Class B? I'm making repairs on my rear suspension. 2017 Roadtrek Versatile 170 on Chevy Express platform. Thanks in advance. Joe

From what I have seen, good track bars are mostly a thing done on coil spring rear axles to keep them in line. There are several different versions/designs used. They also are used on some high perf cornering leaf spring setups also, though.


In general, IMO, I would recommend getting good shocks, proper spring rates both front and rear, and mostly getting a big rear sway bar, if you are trying to improve the handling of your Chevy chassis.


There are quite a few discussions on Chevy handling stuff on this forum for reference so you can find some that relate to whatever issue you may be trying to address.


Chevies handle quite well in stock form, but can be made better with some changes.

[jojobafanzi]

[


In general, IMO, I would recommend getting good shocks, proper spring rates both front and rear, and mostly getting a big rear sway bar, if you are trying to improve the handling of your Chevy chassis.


There are quite a few discussions on Chevy handling stuff on this forum for reference so you can find some that relate to whatever issue you may be trying to address.


Chevies handle quite well in stock form, but can be made better with some changes.[/QUOTE]

Thank you for the input. I have had handling issues from day one and finally have my front end tight and properly aligned. The front end caster camber adjusting cams are a poor design. One upper control arm bolt was not tight and the threads became damaged so as to prevent proper tightening after an alignment was performed. Because of that damaged bolt, the front end would only stay in alignment for a few miles or a few bumps in the road. This was discovered when I replaced the upper control arm bolts and adjusting cams with locking cams. So instead of just turning the bolt and using the pin to move the caster, the cam has to be removed and repositioned for each increment of adjustment. The new cams have holes for the pin instead of a long slot. The front end caster camber can never move again from normal driving. Now with the front end fixed, that brings me to the second issue. The local shop mechanics all tell me the vehicle feels fine but it isn't. They can't drive the vehicle at highway speeds which is where the symptoms amplify. I live on an island that is about 100 miles long and 25 miles wide with over 8 million people on it. Driving the van around town at 30 miles per hour, it may feel ok to someone who has not driven it 75 to 80 miles per hour. When I begin my vacation, it takes me at least three hours to get off the island and another half a day driving to get to a state where the traffic is moving 75 to 80 miles per hour. That's when the misery begins. By that time, I'm exhausted from the vehicle. I can't keep it in the lane and it feels miserable. Drifting and wobbling from side to side. I have had 8 alignments and I have a printout from most of them. Looking at the printout as data reveals that the rear end alignment, which can't be adjusted is always slightly different. Not much and I do realize that the alignment devices are being removed and reinstalled but the change in readings brought me to examining the rear end suspension. The leaf spring and shackle bushings are shot and blown out. Rubber is bulging out where it shouldn't. The rear axle is moving side to side and forward and back. The van weighs 8400 lbs with all persons and gear on board. So the suspension is maxed out all the time. The factory bushings can't take that stress and thus failed probably early in the vans life. The symptoms are getting worse and I can't do another 5000 mile road trip. I have to change the rear bushings at the least. A trac bar may help in the future by preventing the axle from moving sideways but will not help with forward and rearward movement which basically makes the rear an uncontrollable steering axle. That's the wobble and wander that makes me sick. The polyurethane bushings I purchased have a warranty of 750,000 miles so I'm guessing the manufacturer is confident that they hold up well. The Bilstein shocks I installed made a big difference and I recommend that brand. Other brands may perform well. Changing the bushings is well within my ability but I do not have a lift and the tanks have to come out. I'm not happy with having to rely on someone else doing the removal and reinstall but I have no choice. I feel lucky that there is one single RV repair shop on this island. It's about an hour drive away but they agreed to do the job if I leave the vehicle with them for 2 weeks. Hopefully this will fix the issue. Joe

[booster]

Your 170 is probably different by some amount in the rear than our 190 and where the front spring hanger in the rear winds up in relation to the tanks is probably one of those differences as I can get to front hanger on ours through the small storage area door in front of the passenger rear tire.


That said, there might be a way to get the front eye bolt out by cutting off the head if you have enough access to do that with the tank in place. IIRC how it goes together I think the bolt is installed from the outboard side but there is room on the inboard side to pull it out with the hear removed. Hopefully it would be rusted in to spring eye sleeve. Island/beach vehicles can have quite a bit of rust sometimes.


I am surprised that the bushings would be that bad on a 2017, though, as we don't hear about that very often. Our 2007 are original and still fine, as are the rear shackle bushings. We are normally at about 9200# loaded.


What front end alignment settings are you currently at? Being within factory spec is not good enough for best stability on these vans, and many other vehicles.


If you don't have a generator in place behind the rear axle, I would still consider putting in a big rear sway bar as that really settles down the heavy rear weight vans at highway speeds.

[jojobafanzi]

[QUOTE=booster;

That said, there might be a way to get the front eye bolt out by cutting off the head if you have enough access to do that with the tank in place. Island/beach vehicles can have quite a bit of rust sometimes.



What front end alignment settings are you currently at? Being within factory spec is not good enough for best stability on these vans, and many other vehicles.


If you don't have a generator in place behind the rear axle, I would still consider putting in a big rear sway bar as that really settles down the heavy rear weight vans at highway speeds.[/QUOTE]

I have a generator and the caster is set more positive than spec. Vehicle not driven in salt and it is undercoated so its a greasy mess. I'm guessing the RV/ Limo/ Bus repair facility where I will take the RT to in July is used to difficult custom jobs. If I was working there I would look to cut those bolts without dropping tanks. It does look possible to me if I had a lift and it looks like the bolts can be installed with tanks in place. I think the generator will interfere with a sway bar. I'll check... Joe

[booster]

Originally Posted by jojobafanzi

I have a generator and the caster is set more positive than spec. Vehicle not driven in salt and it is undercoated so its a greasy mess. I'm guessing the RV/ Limo/ Bus repair facility where I will take the RT to in July is used to difficult custom jobs. If I was working there I would look to cut those bolts without dropping tanks. It does look possible to me if I had a lift and it looks like the bolts can be installed with tanks in place. I think the generator will interfere with a sway bar. I'll check... Joe

That sounds like how I remembered it. The tank is only and issue in sliding the bolt out to clear the eye so putting the head on the inner side and the nut toward the tank should be fine and is how I also would do it.


As much caster as you can get with .5* more on the right is probably as good as it gets. Having the toe set in by at least 1/8* (old school inch spec rather than degree) makes a very big difference. They get really wandery if toed out at all.



Since you have a generator, the easier install Hellwig sway bar will not fit without some modifications or moving the generator to the rear a couple of inches. The Roadmaster bar has the arms to the rear so can be made to fit around generator, at least on the extended vans and probably yours also. It would probably take some minor tweaking to the link mountings but it has been done by numerous people.


On our 190 we had the generator when I put in the rear bar so I used a circle track race car straight bar and made my own axle brackets. It uses bendable, splined on, arms, so I had more flexibility in mounting it.


It would be interesting to see if your shop has an idea why the rubber bushings would fail so quickly. When I hear gloppy rustproofing I do immediately wonder if that could have contributed if the rubber got sprayed.

[jojobafanzi]

Originally Posted by booster

That sounds like how I remembered it. The tank is only and issue in sliding the bolt out to clear the eye so putting the head on the inner side and the nut toward the tank should be fine and is how I also would do it.




Since you have a generator, the easier install Hellwig sway bar will not fit without some modifications or moving the generator to the rear a couple of inches. The Roadmaster bar has the arms to the rear so can be made to fit around generator, at least on the extended vans and probably yours also. It would probably take some minor tweaking to the link mountings but it has been done by numerous people.


On our 190 we had the generator when I put in the rear bar so I used a circle track race car straight bar and made my own axle brackets. It uses bendable, splined on, arms, so I had more flexibility in mounting it.


It would be interesting to see if your shop has an idea why the rubber bushings would fail so quickly. When I hear gloppy rustproofing I do immediately wonder if that could have contributed if the rubber got sprayed.

I will look into those sway bars if the bushings don't solve the issue. The rubber is so bad, I'm pretty confident that is the issue. I did the undercoating long after the wandering issue. I did that because rust killed my last Coachmen class B. I didn't know any better and I drove it everywhere on salted roads. After 26 years, rust killed it or basically I killed it. Can't stop rust and no body shop on this island will specialize in restoration unless its a classic car. At 26 years old, it was time for a new class B anyway. Parts becoming scarce was a concern to me. I agree that bushings should last a long time. I have driven some of my vans 150,000 miles and never had to replace leaf spring bushings. I will be so happy if the shop cuts the bolts off rather than drop the tanks. Less for me to worry about. Right now everything works as designed.

[jojobafanzi]

Originally Posted by booster

Since you have a generator, the easier install Hellwig sway bar will not fit without some modifications or moving the generator to the rear a couple of inches. The Roadmaster bar has the arms to the rear so can be made to fit around generator, at least on the extended vans and probably yours also. It would probably take some minor tweaking to the link mountings but it has been done by numerous people.


On our 190 we had the generator when I put in the rear bar so I used a circle track race car straight bar and made my own axle brackets. It uses bendable, splined on, arms, so I had more flexibility in mounting it.

Hello Booster. I think I may do the modifications in stages. Can you explain to me why you did your rear sway bar and the suspension modifications you recommend on my ill handling beast? Struck out on my local shops. I still have an appointment at a shop far away. I think I should have them install a rear sway bar and then test the ride before having tanks removed for bushings. Unless they feel confident they can do the bushings without dropping the tanks. Either way, it appears to me that a rear sway bar and or track bar should be on the rear of my vehicle. Thanks in advance. Joe

[booster]

Originally Posted by jojobafanzi

Hello Booster. I think I may do the modifications in stages. Can you explain to me why you did your rear sway bar and the suspension modifications you recommend on my ill handling beast? Struck out on my local shops. I still have an appointment at a shop far away. I think I should have them install a rear sway bar and then test the ride before having tanks removed for bushings. Unless they feel confident they can do the bushings without dropping the tanks. Either way, it appears to me that a rear sway bar and or track bar should be on the rear of my vehicle. Thanks in advance. Joe

There is more detail in other discussions, but the bottom line, IMO, is that the wander and directional stability issues we see in almost all vans, including the Chevies is caused by understeer. This what a Nascar guy would call "push" and it means the front tires are not getting adequate traction to turn the vehicle without sliding some amount. Low front traction makes the front of the van move more in the wind and it also means steering corrections need to be larger to get the same amount of direction change.


Oversteer is affected by a few different things that can be changed.


Tire pressure...Higher front pressures reduces understeer. Lower rear pressure reduces understeer.


Springrates (stiffness)... Softer front springs reduce understeer. Stiffer rear springs reduce understeer.


Shocks...Stiffer shocks that match the springrates can lower body roll and steering geometry changes that come with that roll so reduce understeer.



Caster setting...More caster reduces understeer


Sway bars...Lower sway bar rate (smaller diameter) front swaybar reduces understeer. Higher sway bar rate rear bar reduces understeer.


Finding the best combination of these isn't extremely difficult, but not always the same either (different users define good handling differently)


Tire pressure...Most are using 60-65psi in the front and 80psi in the rear. The 170 could be a bit lower depending on how it feels. The ratio of front to rear is what is important for understeer limiting.


Springrates... Most of us have gone opposite of what is best for understeer reduction by putting higher springrate coils in the front to get lift. Getting the rear with more of the weight on airbags softens the rear which is also opposite. It is worth it for ride improvement, though, and understeer is addressed elsewhere.


Shocks...Most are using Bilseins, but others by happy with others, but don't go cheap or soft.



Caster settings... The most caster you can get is best, as long as you keep .3-.5 degrees more on the right side


Sway bars...A smaller swaybar in the front reduces understeer. A bigger swaybar in the rear reduces understeer. IMO this a one of the best ways to reduce understeer in our vans. They don't change spring rate so the only time they are doing anything is to prevent sway or on one wheel rear bumps when they limit one wheel travel by moving force to the other side. They also reduce body roll in turns or when hit by wind.


As I said before, track bars are not really a good thing for live axle leaf spring setups on the street and I don't think will give you the results you want.


But, don't do any of this unless you fix the loose rear bushings and shackle issues first. How are the control arm bushings in the front and body mounts looking? They would be similar to material of the spring bushing so may also be bad.

[jojobafanzi]

Originally Posted by booster

There is more detail in other discussions, but the bottom line, IMO, is that the wander and directional stability issues we see in almost all vans, including the Chevies is caused by understeer.


As I said before, track bars are not really a good thing for live axle leaf spring setups on the street and I don't think will give you the results you want.


But, don't do any of this unless you fix the loose rear bushings and shackle issues first. How are the control arm bushings in the front and body mounts looking? They would be similar to material of the spring bushing so may also be bad.

That picture is of a shackle bushing but the uneven rubber bulge is present on the spring eye bushings as well. Hard to get a good picture, I need to make better ramps. The side to side motion is not related to wind but wind does make it worse. I have been on a flat highway with zero wind and the vehicle is moving side to side and makes me sick after a while and its exhausting to drive. Not normal. Add wind and speed and the symptoms are amplified. I'm guessing from what I read, most Roadtrek owners have had this issue and spent time and money to correct it. Body mount bushings all look great. Control arm bushings I just had inspected and I replaced the upper control are bolts and caster adjusting cams with locking cams so the alignment will not go out. I will call the shop today and discuss handling issues with them. They are a truck , limo and bus shop. I will have them install a big sway bar that fits. Joe

[booster]

Originally Posted by jojobafanzi

That picture is of a shackle bushing but the uneven rubber bulge is present on the spring eye bushings as well. Hard to get a good picture, I need to make better ramps. The side to side motion is not related to wind but wind does make it worse. I have been on a flat highway with zero wind and the vehicle is moving side to side and makes me sick after a while and its exhausting to drive. Not normal. Add wind and speed and the symptoms are amplified. I'm guessing from what I read, most Roadtrek owners have had this issue and spent time and money to correct it. Body mount bushings all look great. Control arm bushings I just had inspected and I replaced the upper control are bolts and caster adjusting cams with locking cams so the alignment will not go out. I will call the shop today and discuss handling issues with them. They are a truck , limo and bus shop. I will have them install a big sway bar that fits. Joe

There are several reasons for side to side motion of the van, but mostly it comes from understeer reactions to minor disruptions of the van from the road, wind, or other vehicles. Big tall vans always will be worse than a car in that respect. I am very sensitive to that kind of handling and our van was like that stock, even many other users have no problem with that kind of handling. That is why I did so much work to ours to get rid of the understeer. You may be like I am for handling evaluation.



If you are feeling it with no wind it is very common, and getting more so lately. I think that the disruption may be from grooved highway lanes. Blacktop is usually the worst, but concrete does it also. If you have two tire track grooves in the roadway you can constantly bounce off of 4 different surfaces and all will require correction. Our van handles extremely well for a heavy van, but I feel it when driving on a grooved road and it does make for more work even with the very small corrections our van needs to get back in line. The more oversteer you have, the worse it will be because of the larger corrections needed. Usually, I am able to find out roughly where the groove is and try to stay in the middle, but you do have to hold a very good line to stay there.



The same can happen if you have soft sidewall tires and/or the tires are underinflated. Sidewall flex allows the vehicle to move side to side and if you have understeer that flex usually doesn't match front to rear so you feel like you are turned.


Before you start chasing a moving axle scenario I really think it needs to be confirmed that it is moving back and forth more than normal. If the front bushings look like the shackles, I don't think they look that bad as bushings always stand proud from the spring or sleeve and often get misshapen like that. The most the spring can move would be to hit the mount and you almost certainly would feel it and you would have visible rub marks where it hit.


The shop will be able to get it on a drive on rack, I hope and pry the axle back and forth or have helpers push the van side to side. They should be able to conclusively say the axle is looser than normal, or not.


I am sure they will also check the steering gear for tightness of the adjustment and also the mounting bolts to the frame.

[phantomjock]

jojobafanzi -

I just noted your issues, sorry for the "late join." My quick review of the thread, I concur with the vectors booster has offered. I have a couple of questions that would help me better understanding of where you are and what you have going on:
1. It is a 2017 Chevy based platform. Are you the Original Owner?
2. You've had these issues since Day One. Was that rolling out of the dealership - or off the lot? Was the price "better than it should be?"
3. Do you have a vehicle history report? (Any chance the chassis could be "tweaked?")
4. How many miles on the rig?
5. What is the status of the shocks? Its work to pull them, but a bowling ball test would tell you if one is not working as the others. While just looking at the shocks - you could check teh Bump Stops. Mine ar trash. That is one reason I'm working on suspension this week. Based on mileage consider new shocks at 40-50K, your mileage may vary. DO the bump stops then too.
6. When were the tires last spun balanced? booster has addressed sidewall, etc. How many miles on these tires? If they came with the rig - time to swap them out - you are over the 6 year point. Are they E-Rated? If not that in definately - Not Good. Do they have a "radical" off-road tread? Any possibility they have been rotated (inapproprately)? Tire road interface can give that drifty feeling as booster mentioned with varing pavements, groves, etc. Are the wheels true?

I'll suggest 2 more.

Also, have you checked out any of the other Chevy sites? Sure, a lot are business vans - but they get a lot of miles and heavy loads. Might be some joy there. This one is specifically the Chevy Express Forum (GMC Savana):
https://www.gmtruckclub.com/forums/c...-savana.17719/
I've found some useful information there. Also there are a few free mechanics assistance sites you can use as a sounding board. I found these guys helpful:
https://www.2carpros.com/

Not a prescription - but what I'd do after answering all of the above:

This offering involves some physical work. Easy enough, and you can do without paying a high class shop. First I'd Square the vehicle. Load it up,and get the corner weights as accurate as possible at each tire, move stuff inside if you can live with the relocation. [You'll need to find a scale, weigh station.] Make sure the air pressures are all set to spec. Then I'd check the ride heights at all 4 corners. Again, accurate and level ground would give you some real clues. This could be telling if the rig is way out of balance. Can't say you'd get the same symptoms, but it pays to get as close as possible. {these might be things the bus-shop could do for you too}
You could do your own toe and alignment check but pretty detailed, but do-able. Note I said - check - not align!

I guess I'd say I'm really lucky, as I've not experienced any of these issues with my 170. This week I'm getting ready to do some self-inflicted pain with a moderate chassis rise, new bump stops all around, and a spring lifts front and rear. I'll be doing all those steps I suggested; Scale the chassis, check ride height, etc. so I'm gonna' take my own medicine.

bottomline: there is a LOT I'd do before thinking about a track bar. Is this something a shop has recommended?

Best of luck. Please know we are feeling your pain.

Cheers - Jim

[jojobafanzi]

Originally Posted by phantomjock

jojobafanzi -

1. It is a 2017 Chevy based platform. Are you the Original Owner?

2. You've had these issues since Day One. Was that rolling out of the dealership - or off the lot? Was the price "better than it should be?"

3. Do you have a vehicle history report? (Any chance the chassis could be "tweaked?")

4. How many miles on the rig?

5. What is the status of the shocks? Its work to pull them, but a bowling ball test would tell you if one is not working as the others. While just looking at the shocks - .





Best of luck. Please know we are feeling your pain.

Cheers - Jim

----No! Bought from original owner and we are in same circles. Told me he always hated the ride and bought it specifically so his wife had a toilet for long road trip his family took two times per year. He put 13,000 miles on it and then had a custom sprinter passenger van built with a large bathroom across the rear that better suited his large family traveling needs. Absolutely nothing in the vehicle was ever used when I purchased it except the toilet.
----He had it built and titled it before he drove it. He said he would have refused it or demanded dealer fix the handling issues if he had not already titled it.
----No accidents reported and underside of the vehicle and interior were close to showroom condition.
----I purchased at 13,400 miles and now has 38,000 miles on it. I replaced the tires with Micheline Aguilis and Bilstein shocks. Improved the ride a bit. Alignment was constantly going out and I replaced the caster adjusting cams to locking cams so alignment can't go out. During this procedure, I discovered a damaged upper control arm bolt that was allowing the alignment to go out and the van became towed out in just a few miles. Upper control arm bolts were replaced at this time. Got a good alignment at Tampa Spring and the handling is now about 80% better than it was at its worst.
----Not sure of what a bowling ball test is. Shocks feel great. Bump stops look great. Ride is not too harsh but gets harsh if I over inflate the tires. Michelin website has a chart for pressure as per axle weight. I put it to their specs which is 42 front and 62 rear. Pressure goes up as tires heat up to 47 and 67. If i Put 60 and 80, the vehicle bounces and is unsafe to drive. Tires were balanced by a pro. Took an hour. Load range E tires. Axle weights are 3700 lb front and 4760 with all persons and gear and dog on board.
--------I have been reading forums like you suggested and thank you for that. I have found that most motorhomes built on a base platform from another manufacturer do not upgrade the suspension of the base vehicle to keep cost down. Some motorhomes handle fine and some do not. I am not alone. The conclusion is that I have to do suspension upgrades that Booster has suggested and you and many others. My local shops won't do this as I live in a resort area but I found a Truck / Bus and RV shop that does this work and actually builds Buses. I am going to drop of the Roadtrek for two weeks and they will do the upgrades in increments. Probably starting with the sway bar. Rear sway bar is a term that I can't count how many times I have read this. Everyone recommends a rear sway bar so I think I will start there. Thanks for taking interest. The Roadtrek is driving much better with the work I have done, just not good enough to drive long distances at high speed. Joe

[phantomjock]

Joe -

I find your situation interesting and have had a look around to better understand the how and why of the problem. I've done a bit more looking, and here is another Q&A forum that you could ask about the suspension:

https://repairpal.com/questions/chevrolet/express-2500

Can't say if it will be helpful, but worth a shot.

The Bowling Ball test, is just a weight on a shock, removed obviously, and the weight released and the time recorded. Sort of a timing drop-test. A good way (not easy) to check the similarity of all 4 shocks. A similar simple compressiopn test could point out any differences too. That the shocks are fairly new, maybe don't need to these checks. The Bilsteins "should" be good for a while, and they also seem to be the "go-to" choice.

Here is an interesting "coincidence" I saw on the chevy forum:

Found something interesting. I changed out the steel wheels for aluminum. The aluminum wheels have the same bolt pattern but a different offset the OE wheels have a 18-22 offset and the pickup wheels I installed have a 28mm offset.Could this be an issue? My alignment guy says its possible it is causing the wander.

There are 5 pages in that thread, you might want to check out:
https://chevroletforum.com/forum/exp...wander-115076/

That you have found a shop to do the work is good, and doing in increments it will be good to follow your efforts.

Before and after pictures of the sway bar install on a 170 (Chevy 2500) would be good to have on the forum for other users.

Best of luck.

Cheers - Jim

[booster]

We had a parallel thread here on that.


https://www.classbforum.com/forums/f...way-14460.html

[phantomjock]

Ya' know - I shoulda' looked.
Seems like the same member too; jjrbus... 'splains a lot!

Corporate memory, booster - keeping me "honest!"

Cheers - jIM

[jojobafanzi]

Originally Posted by booster

There are several reasons for side to side motion of the van,

Before you start chasing a moving axle scenario I really think it needs to be confirmed that it is moving back and forth more than normal. If the front bushings look like the shackles, I don't think they look that bad as bushings always stand proud from the spring or sleeve and often get misshapen like that. The most the spring can move would be to hit the mount and you almost certainly would feel it and you would have visible rub marks where it hit.


The shop will be able to get it on a drive on rack, I hope and pry the axle back and forth or have helpers push the van side to side. They should be able to conclusively say the axle is looser than normal, or not.


I am sure they will also check the steering gear for tightness of the adjustment and also the mounting bolts to the frame.

Booster. I finally got the RV shop an hour away to take on my project. They agreed with your opinion that the leaf spring bushings and shackle bushings in the rear are not that bad. We decided to make changes in increments and leave the spring bushings alone. With much complaining, the shop manager agreed to start with a heavy duty rear sway bar since I didn't have a sway bar at all. I requested 1.5" with polyurethane bushings. There is no aftermarket trac bar for the Express 2500 with box frame. The shop installed a factory GM sway bar (85607964) 1.25" with rubber bushings. They made frame mounts for the links from rectangle stock. The shop moved the generator rearward 2". This took them 1 month to the day. I drove it home on a very windy day and the sway from wind was greatly reduced and cornering and handling was greatly improved. After the wind subsided, I got a better feel of the van. Overall, a much better ride but the rear end wagging is still there although not as bad. The front end is still tight and now I am at the next step which is a rear trac bar (Panhard bar). Since the generator is no longer in the way, I can get the van up on ramps and I am in the process of fabricating my own trac bar and installing it myself. Most parts are ordered and should arrive in about 10 days. I will keep you posted on the progress. Joe

[jjrbus]

After several inspections and alignments I found that the average alignment tech does not know how to align the older vans. Once I was at a knowledgeable tech it took him 2 min to find an issue! The punch outs for the cam and caster kits were not completely removed. This was my 6th front end alignment!!!!

I was down to it is either the tires or the wheels and tried OE steel wheels with some used tires. Night and day, could tell right out of the driveway that it handled different. Put the new tires on the steel wheels and problem solved. Just sold the aftermarket wheels to a guy putting them on a trailer yesterday.

[booster]

Originally Posted by jojobafanzi

Booster. I finally got the RV shop an hour away to take on my project. They agreed with your opinion that the leaf spring bushings and shackle bushings in the rear are not that bad. We decided to make changes in increments and leave the spring bushings alone. With much complaining, the shop manager agreed to start with a heavy duty rear sway bar since I didn't have a sway bar at all. I requested 1.5" with polyurethane bushings. There is no aftermarket trac bar for the Express 2500 with box frame. The shop installed a factory GM sway bar (85607964) 1.25" with rubber bushings. They made frame mounts for the links from rectangle stock. The shop moved the generator rearward 2". This took them 1 month to the day. I drove it home on a very windy day and the sway from wind was greatly reduced and cornering and handling was greatly improved. After the wind subsided, I got a better feel of the van. Overall, a much better ride but the rear end wagging is still there although not as bad. The front end is still tight and now I am at the next step which is a rear trac bar (Panhard bar). Since the generator is no longer in the way, I can get the van up on ramps and I am in the process of fabricating my own trac bar and installing it myself. Most parts are ordered and should arrive in about 10 days. I will keep you posted on the progress. Joe

Glad it got better for you. 1 1/4" will probably be fine with a 2500 van that has IIRC 8600# gross weight unless you tow and then I would go bigger.

The shop could have just gotten a Hellwig or Supersteer swaybar and just welded the brackets to the frame without making anything, though.

The same is true about using the Supersteer Trac Bar, just weld the brackets to the frame.

I hope you will not be disappointed with the track bar as the leaf spring setups don't normally need one, even on the heavier vans like we have. Be aware that fitting a track bar on leaf spring setups properly involves getting the "roll center" of the track bar in as close to same point as the roll center of the rear springs and axle. If they are at different points you can wind up with funny turning right vs left where the don't behave the same. Binding is also a big deal with leaf spring setups and the tighter the bushings are the worse it will be. Nearly all of the information I saw said that if you use a trac bar on leaf springs for the street, not racing, it should have big soft bushings to prevent binding, not solid or even urethane. Of course that allows more travel also, though.

I have a feeling that you may just be feeling sidewall flexing which allow the tread to move in reference to rest of the vehicle. On heavy vehicles it can be quite a lot, especially if you are driving on a road with the two worn tracks in the tire lanes. A road like that can make you think you have a handling problem when it is the mismatch of the track width of the van to the grooves or moving side to side in the grooves. The van will feel like it is wiggling down the road. I think we all have felt that on occasion in our vans, but big swaybars and shocks, plus relatively stiff sidewall tires minimizes it. What tire are you using?

[jojobafanzi]

Originally Posted by booster

Glad it got better for you. 1 1/4" will probably be fine with a 2500 van that has IIRC 8600# gross weight unless you tow and then I would go bigger.

The shop could have just gotten a Hellwig or Supersteer swaybar and just welded the brackets to the frame without making anything, though.

The same is true about using the Supersteer Trac Bar, just weld the brackets to the frame.

I hope you will not be disappointed with the track bar as the leaf spring setups don't normally need one, even on the heavier vans like we have. Be aware that fitting a track bar on leaf spring setups properly involves getting the "roll center" of the track bar in as close to same point as the roll center of the rear springs and axle. If they are at different points you can wind up with funny turning right vs left where the don't behave the same. Binding is also a big deal with leaf spring setups and the tighter the bushings are the worse it will be. Nearly all of the information I saw said that if you use a trac bar on leaf springs for the street, not racing, it should have big soft bushings to prevent binding, not solid or even urethane. Of course that allows more travel also, though.

I have a feeling that you may just be feeling sidewall flexing which allow the tread to move in reference to rest of the vehicle. On heavy vehicles it can be quite a lot, especially if you are driving on a road with the two worn tracks in the tire lanes. A road like that can make you think you have a handling problem when it is the mismatch of the track width of the van to the grooves or moving side to side in the grooves. The van will feel like it is wiggling down the road. I think we all have felt that on occasion in our vans, but big swaybars and shocks, plus relatively stiff sidewall tires minimizes it. What tire are you using?

The tires are Michelin Agilis Cross Climate Load range E. I have tried different tires and high pressures. Going 80 psi tires in the rear just made the vehicle bounce. I'm not against going with a larger rim and a lower profile tire but I would need advice on what to choose and I don't want to make the ride more harsh than it already is. If trac bar is a flop, I can always remove it and the next step will be tires and rims. I requested the Hellwig sway bar but this is NY and they installed something else. The shop spent under $200 on materials and charged $4184.63. Most likely trying to maximize profit. Spending $650.00 on a Hellwig kit was too easy for them. As for the Hellwig trac bar, Hellwig doesnt make a kit for the 2500. I asked many questions when I called Hellwig and possible solutions a while back and they are too busy to call me back. Last request I made was about a week ago. I was informed the person I need to speak to was out of town on a rally for a while. I started my own R&D for making my own trac bar. The maximum upward travel of the suspension is 2.5" until contact is made with the bump stops. I'm not sure how much the arc in suspension travel will affect the handling and if polyurethane bushings will be too tight. Hellwig uses polyurethane.I can always swap out to rubber bushings. Certainly an easy task. I am not driving a race car so I'm planning on installing the trac bar perfectly horizontal and parallel with the axle. The length of my trac bar will be about the same as the Hellwig and at about the same locations on the frame and on the axle tube. My only difference I was planning is mounting the trac bar slightly rearward of the axle tube instead of directly over the center of the axle tube. The leaf springs being mounted to the frame in the front should prevent any change in the direction the rear axle is pointing. If you think this install will not function, I'm all ears. Please explain how Roll Center will play in this application? I really don't want to create a monster. Also, the point on the rear axle tube where Hellwig bolts their trac bar to is tapered on my axle and a different diameter than the 3500. Also there is very little distance from my axle center section and the floor of the vehicle. Your input is greatly appreciated. Joe