Some advice on a Chevy Suspension Upgrade

[booster]

Originally Posted by mangomike

I had an interesting discussion with "Chevy guy" yesterday
it seems like in the discussion we(and from everything I've read here) pretty much decided that roadtrek gone on the cheap and not upgraded the suspension.
So at the end of a long discussion his question was ,,,,, I I simply didn't replace the springs front and back ,,,, the Chevy 1 ton or heavy duty OEM equipment. Rather than going the airbag, sway bar route. I guess that's basically what folks have been doing when putting in better Springs and shocks. But is there such a thing as a one ton Chevy express? I have found 4500 but it doesn't seem to have come in the express. I'm just thinking that OEM might be easier if they're still available. What do you think?
going to a suspension shop on Thursday for a diagnostic look.
Thanks for everyone's help
m

The Chevy Express 3500 used on the Roadtreks, except the 170, is a one ton van and the biggest they make in the full bodied vans and it also comes cutways up to 1 ton in the same light truck series. The 4500 is a commercial mid duty truck built as a cutaway. It is possible the font springs might be able to be used, but in searching in the past that option never showed up. The rear springs are normally different on any of the cutaways.


The other part of it would be that even if the GM parts were available, the only way they would be, maybe, cheaper would be used ones. Used springs tend to be a not very good thing in my experience.



When we were getting custom front springs made, they were pretty expensive, but the Moog fronts aren't all the bad. The biggest cost is labor in most cases. If you went with either a rearch of leaf add in the rear, it would be the least expensive, but even a new set of right rate, 2" higher, rear springs is not horrible in the aftermarket. Airbags don't get real expensive unless you go for an onboard compressor and controls that can over double the cost, but air bags have, IMO, lots of advantages over spring changes.


Shocks are interesting because you can get quite inexpensive firm control shocks, but they ride bad. You can get inexpensive soft shocks that handle worse. Or you can spend more for good variable rate shocks like Bilstein or Fox, that are pretty good at both. Everyone has their own cost benefit assessment to do on shocks for those reasons.


The swaybar question will likely cause a bit of blowback, but I think that there has been quite a bit of comments on the need, or benefits, of having a big rear bar. I totally understand that for some people the other improvements like shocks, tires, etc may improve things enough that they are OK with the handling, which is certainly their choice, but it does not say anything about how effective a rear bar is in improving things. We have a decade of experimenting with nearly all the suspension changes on Chevies, including driving ours with rear bar connected and then the same drive and conditions with the links disconnected to get a "for sure" feel for the changes. IMO, the rear bar is the top improvement for both sway and directional stability, assuming the front end parts are good and properly aligned.


Here is my feeling for what the various changes do for a Chevy, by category of problems,


Sway: Rear bar most improvement, shocks second, springs third


Directional stability and response: Rear bar most, tires second, lift third (improved steering geometry), fourth could be getting rid of the wrong offset wheels if you have them



Ride quality: Lift first to get off overloads and bump stops, tires next if Defenders or other comfortable tire, airbags third, spring changes-especially in the rear can make comfort worse by some amount-the Moog springs are not bad that way but some might notice



Height and clearance: Lift by whatever method


Of course, handling and ride are extremely subjective, as we have found out over the years here, so everyone needs to take their own preferences into account.


Do you think a BMW steering feels right for response without feeling twitchy? If so you want to go the most responsive end of the changes


If you think the BMW is twitchy and difficult to keep in line you want to back off the on the responsiveness a little. This can often be done with just tire pressure if you get it too responsive.


Another observation that I think helps indicate how responsive you want the handling would be how you prefer to hold the steering wheel. I have been asking people about that lately so is kind of interesting.



I am a lazy driver, preferring one hand laid lightly on the lower parts of the steering wheel or spoke. This makes large steering corrections difficult as I don't have a lot of hand motion available. Quick response and small inputs are required, so I have our van setup for as quick as I can steering response. The light touch does give a bit better steering feedback also so more indication of things going on.


Lots of drivers use a tight grip with both hands on the mid to upper parts of the wheel and it appears that holding the wheel that way seems to inherently give larger steering wheel motions. Perhaps it is because each hand has only half the force needed, or the tighter grip and tensed muscles, I don't know, but that style would tend to find our van too quick to react and harder to keep a straight line because of constant slight overcorrections. It may be the same type of thing that happens in the super light force steering of the old American rear drive cars that were very hard to keep in line. A reduction in steering response would likely be desirable for these drivers.


As I said earlier, it is very personal and subjective, and it is almost certain that some folks will be disappointed, especially if they just duplicate other systems without considering the big picture.

[rivers2run]

I just had my Roadtrek p210 lifted. I went to a place in Dixon California Valley Springworks they make their own springs. They work mostly on those big utility trucks the power companies use. I got a 2 inch lift they replaced my front springs and re arced rear leaf springs and added a leaf. We replaced all shocks with KYB gas adjust cost around $1350 which I thought was very fair. I am absolutely delight it handles so much better stopped the sway, it just heads down the road with minimal correcting when truck pass. Much better all around. The bump stop is off the frame. Good place they know what they are doing. It really improved the weight capacity of my P210 wish Roadtrek would upgrade those suspensions especially the P210 which are so heavy.

[booster]

Originally Posted by rivers2run

I just had my Roadtrek p210 lifted. I went to a place in Dixon California Valley Springworks they make their own springs. They work mostly on those big utility trucks the power companies use. I got a 2 inch lift they replaced my front springs and re arced rear leaf springs and added a leaf. We replaced all shocks with KYB gas adjust cost around $1350 which I thought was very fair. I am absolutely delight it handles so much better stopped the sway, it just heads down the road with minimal correcting when truck pass. Much better all around. The bump stop is off the frame. Good place they know what they are doing. It really improved the weight capacity of my P210 wish Roadtrek would upgrade those suspensions especially the P210 which are so heavy.

Valley is Bill Erb, who has had lots of of discussion here, for reference.


What did you wind up with for front wheelwell heights? They have tended to run pretty high lately from them, and the set I tested in our 190 was at nearly 38" in the front (2" higher than they said it would be) with very little downtravel left.

[rivers2run]

I got 35 inches in the front. He said they had changed the gauge a bit.

[booster]

Originally Posted by rivers2run

I got 35 inches in the front. He said they had changed the gauge a bit.

That is in a much better range, for sure. It is good that they wised up to that. Most that use the Moogs get about 35.5" plus or minus so very close. The 210s can run higher or lower than the 190s or other brand Chevies because of the big overhand in back that is more prone to changing the front height based on how much and where the load in th van is.

[mangomike]

okay, I went to the suspension shop that had received the best reviews ,,,their findings are that the back seems to be okay, the front is sitting on the bump stops.,,,, their suggestions were/are
start by putting on 4 heavy-duty shocks ,,, they priced out NAPA HD shocks and the labor to install them at $ 750 ...out the door.,,, Including labor, taxes etc.
that seems a little high to me ,but I don't know.. They didn't really want to show me the estimate so I don't know how much was labor and how much was parts.
Anyway, I told them that I wanted to look into Bilstein or other upgraded shops.
I had said I would let you all know about our progress, so that's about it.
I think that we will start with installing the shocks ,,, any suggestions on the company,model ,pricing , would be greatly appreciated.
Hope to get this done sometime in the next couple weeks.
Thanks everybody for your patience and your help
Michael

[booster]

I am a bit surprised they would say the rear was OK, as most are on or very, very, near the overload leaf which can really be a bad influence on ride quality.

[Rockwood27]

The list price of NAPA front shocks is roughly $100 and rears are $45-100. You may also need new bushings. So you have about $350-400 in parts ($200-250 wholesale) and the rest is labor. I can't see how installing shocks will get you off of the bump stops. I also agree with the above. The rear should also be squatting.

[mangomike]

I'm not sure that I can shed any light on the rear ,,,, except when we did our measurement the rear was at 36 in.+ and the front was at 33 + .... So maybe there has been some work already done one the rear?????? We are were partially loaded ,water in tanks ect. when we measured.
As to the front and bump stop. I hate to sound so ignorant (but I am) the thought is that the new shocks will not raise the front up off the bump stop ?????..... that is the spring job?????
If that is so then I may have the wrong people looking at the problem?
I was so ready to solve this problem and move on to the Fridge!
Thanks all
m

[booster]

Originally Posted by mangomike

I'm not sure that I can shed any light on the rear ,,,, except when we did our measurement the rear was at 36 in.+ and the front was at 33 + .... So maybe there has been some work already done one the rear?????? We are were partially loaded ,water in tanks ect. when we measured.
As to the front and bump stop. I hate to sound so ignorant (but I am) the thought is that the new shocks will not raise the front up off the bump stop ?????..... that is the spring job?????
If that is so then I may have the wrong people looking at the problem?
I was so ready to solve this problem and move on to the Fridge!
Thanks all
m

On a 210 you already have lift blocks in the rear, which can put wheel wells at a height that looks OK, but you can still be bottomed on the overload spring. Here is a pic from another thread that shows where to look to see if you are. It is basically just in front of the rear wheel where the shorter bottom overload leaf comes up by the the regular spring above it at the end. It should not touch or be even closer than about 1/8" if you can help it.






Just look at the size of that bottom leaf. You don't want to be hitting it on bumps as it is like hitting a solid stop it is so firm and progressive. Ignore pretty much all other measurements in the rear for now, as this one is the one that counts.


The springs set the front height for the most part, not the shocks. Only if you have extremely high pressure gas shocks will they raise it at all, and those aren't the ones you are looking at, and shouldn't be.


If the folks you have looking at the van don't understand this, they would be the wrong ones to use, especially if you get into more than shocks later.

[rivers2run]

Yes thats what Bill Erb said it is the springs that do the heavy lifting. My front was lower and now they are about the same height 35- 35.5 inches front and back. Off the bump stop. New springs in the front, add a leaf and re-arced in the rear and new shocks $1350. P210. photos of my front and rear just after being done. http://www.classbforum.com/forums/me...albums182.html

[booster]

Originally Posted by rivers2run

Yes thats what Bill Erb said it is the springs that do the heavy lifting. My front was lower and now they are about the same height 35- 35.5 inches front and back. Off the bump stop. New springs in the front, add a leaf and re-arced in the rear and new shocks $1350. P210. photos of my front and rear just after being done. Class B Forums - rivers2run's Album: P210 front and rear bump stop after spring replacement

Did he add an extra or larger leaf on the driver side rear to get you level? He told me he almost always had to do that on the Chevies, and most of us with airbags have found we need extra pressure on the that side unless other changes are also made.

[rivers2run]

Yep he noticed it was sagging drivers side rear he added a leaf on both sides it might have been bigger on the driver side. The big gas tank is on that side so that added weight might be doing it. Handles so much better no one sits in the rear so I have no idea how it rides.

[mangomike]

Ok ,,, so I went over to the van and looked/ measured the space between the overleaf and the regular springs. It measures between 3/16 and a 1/4 inch. I had my wife sit on the bed directly over the springs (lets say around 135 lbs) no change. I had her jump up and down ,,, no change . Now I know her weight is nothing like driving down the road and the vans weight bounce up and down ,,, but not changing seemed good . I'm going to try another place that has been recommend to me ,,, see what they have to say.
thanks
michael

[booster]

Originally Posted by mangomike

Ok ,,, so I went over to the van and looked/ measured the space between the overleaf and the regular springs. It measures between 3/16 and a 1/4 inch. I had my wife sit on the bed directly over the springs (lets say around 135 lbs) no change. I had her jump up and down ,,, no change . Now I know her weight is nothing like driving down the road and the vans weight bounce up and down ,,, but not changing seemed good . I'm going to try another place that has been recommend to me ,,, see what they have to say.
thanks
michael

That is really interesting, as I can't ever remember anyone having a stock Chevy with anywhere near that much clearance on the overload leaf.



If you get a chance and can get in close enough, it would be nice if you could get a pic of the the area shown in the pic earlier from the other thread. The area in front of the axle right at the end of the overload would be the best area. At that far off, it makes one wonder is someone has done a modification to something, as it is pretty unusual.

[markopolo]

1/4" overload leaf clearance on mine is with 50psi or 60psi in the air bags!

[mangomike]

Maybe I measured the wrong place? I still can't get photo into the body of a post ,but I acd them to my album ... trim height .. I think that album is available to everyone?
Thanks for all your help
Michael

[rivers2run]

One thing Bill Erb did was raise the front first then he took measurements and decided if the rear needed work. He didn't want to make any determinations until he had seen what lifting the front did. As it turned out it did especially the drivers side. You might be a bit skeptical if someone makes full assessment right off the bat.

[markopolo]

I'd say the leaf pack is resting on the overload leaf but I see how you could think it is off it because of the gap. My van is an older model than yours but it looks like this: http://www.classbforum.com/forums/f8...html#post39481

I don't think you necessarily need to be up off the overload leaf as shown in my photo but you see a bit of curvature of the pack whereas yours looks a bit flat to me.

[booster]

Good pix, very clear. You are looking at the space between the steel portions of each leaf, but they actually come together at the roundish "bumper cushion" further to the end of the overload leaf.


You look to be either sitting on that cushion with the spring pack or very close to it, which is what we normally, so very typical of a 210.


The cushion also looks to be pretty well beat up, so it has been hitting pretty hard for quite while.


The fact that you are sitting on that huge overload leaf would help explain why the van didn't move when your wife was jumping up and down inside the van. That leaf will limit travel to nearly none so very harsh ride and pitchy.



Getting off the overload with air bags, or getting rid of the overload by doing a proper weight designed complete pack will help things a whole lot, I think.