Sumo Springs bumpstops for Chev 3500 front

[booster]

Originally Posted by KurtFranz

Mike-

Getting ready to take the plunge.... I have an 02C190 - I am assuming that the same items that worked on your 05 will suffice for me as well.

If anyone has bad news for me based on actual experience please let me know.

Thanks!

An 02 is probably the previous generation of Chevy van. If it has a 5.7 or 8.1 and not a 6.0 that is the sure fire clue.


With the model change the modified the front end to make engine compartment smaller and got more room for the front suspension. That allows for longer control arms and springs to improve handling and ride.


So, it is very possible that Sumos on an 02 will behave differently than later models, so be aware of that.

[KurtFranz]

This will be a no go for the fronts as the setup is completely different on the 96-02 generation. The bump stops on these are mounted on the control arm not the frame. May opt for air suspension on the rear, some new shocks and tires and call it a day. The ride is really great on the flat, but the lean on turns needs to be reduced a bit. Maybe a sway bar is in the works if one exists.

Or maybe sell it and buy a new promaster, throw a mattress in there along with a portable toilet, some plastic bins, a collapsible water jug and bucket and call it a day

[TX-Trek]

Booster and others here were instrumental in assisting with a direction to go in regards to the suspension changes I made in our 210. Night and day difference, no rear swaybar yet.

Even though ours is a 2010 3500, there may be useful info here for your model year:
https://www.classbforum.com/forums/f...des-13041.html

Originally Posted by booster

Anything you do to the weight support areas such as Sumos, new springs, spacers, shocks, etc are totally different from what swaybars do. Stiffening up or damping more in weight support may reduce sway a bit, but that is generally not the prime reason for them. Ride height, ride comfort, up and down motion control of the wheels to keep the tires on the road well are the prime things. Any improvements are from the increased stiffness and damping which tend to limit suspension travel


Swaybars are totally different as they support no weight of the van at all. They do absolutely nothing on a smooth road in no wind or other disturbances. The only thing the do is prevent sway of vehicle side to side by making the wheels share more equally any side to side loads. If you have a big wind gust hit the van in the side with no sway bar, the side hit will tend to go up a bit and opposite side will go down, tilting the van and trying to steer it on top of just force of the wind pushing it over. One side tire looses some traction and the other side gains some so can cause a pull also. The same wind with a sway bar on each end of the vehicle will take the extra load on the non wind side wheel and share a lot of it with the wind side, keeping the van more level and tires more equally loaded. preventing a lot of the push from the wind and then the sway back when the wind drops again. Swaybars can increase bump harshness some but only on bigbumps that hit on one side of the van. They will help prevent the van from going off straight ahead in those bumps, though.



The second thing that swaybars do is to balance the traction from from to rear by shifting available traction end to end. How they do it is complicated, but the "rules" are pretty simple. Basically the bigger the swabar is one end, the more traction it gives the the other end. This sounds backwards but is the way it works out. Adding a rear bar to a Chevy RV will transfer traction to the front and that will greatly improve the way the van reacts to inputs form the steering wheel. That improvement means smaller corrections in the steering to keep the van going straight after things like wind gusts. Vans usually come with no rear bars because they are light in the back before conversion to an RV when the get very heavy in the back, so rear traction loss is not an issue like it would be with light rear empty van.


Some users have been just fine with just adding Sumos as the Chevies are quite good to begin with and just getting the van up off the overload leafs in the rear springs with the Sumos will reduce the quite violent "pitching" you can get on bumps, or with hard wind hits, because of sitting on the rock hard overload leafs. Others like me prefer to add a bar and either Sumos or other ways of lifting to improve the steering response to make easier driving. The whole thing with tuning the steering response is very personal choice driven. Some prefer a vehicle to react a bit slowly to prevent overcorrecting all the time. Two hand firm on the wheel all the time folks tend to be that way, I think, and might find a quicker responding van like ours to be too twitchy. More light on wheel, often one handers like me, prefer the small and easy to make corrections.


IMO, do the Sumos if that is your suspension side preference and make sure to replace or confirm that the shocks are good. There are several brands the folks recommend that will improve ride and handling. Our preference is Bilsteins. Make sure you have what you find to be optimum tire pressures for you preference. Most like around 65/80 or so. Make sure it is aligned well and as near to optimum as you can get somebody to do (hard to find these days). Optimum settings are stated in many discussion on this forum.


If you still would like to reduce wind, truck, bump influences you could then put in a rear bar of at 1 3/8" diameter. Don't ever just increase the front swaybar size in the RV vans as it will make handling worse in most cases, and don't increase the front size when you add a rear bar as it negates some of the rear bar benefits.

[KurtFranz]

Thanks - I just want to figure out a way for the van to not lean when I turn. I want it perfectly level when turning a corner at a normal speed. I can't stand the lean. If I cant get rid of it I may sell the damn thing

[booster]

Originally Posted by KurtFranz

Thanks - I just want to figure out a way for the van to not lean when I turn. I want it perfectly level when turning a corner at a normal speed. I can't stand the lean. If I cant get rid of it I may sell the damn thing

I think that wanting zero lean in a tall heavy van, or really any vehicle that isn't sprung so hard it rides like buckboard, is not really practical. I do know that you can get rid of a lot of it, though, with a big swaybar in the rear where the most weight is.


We currently have a 1.5" diameter circle track straight bar in ours and it makes the van quite flat and with excellent lack of understeer in corners. This is with the big Chevy overload removed which makes the rear ride much smoother with airbags replacing the overloads to make higher and softer ride at the same time. I am very happy with handling and ride now, and I am extremely picky on those things.

[KurtFranz]

Originally Posted by booster

I think that wanting zero lean in a tall heavy van, or really any vehicle that isn't sprung so hard it rides like buckboard, is not really practical. I do know that you can get rid of a lot of it, though, with a big swaybar in the rear where the most weight is.


We currently have a 1.5" diameter circle track straight bar in ours and it makes the van quite flat and with excellent lack of understeer in corners. This is with the big Chevy overload removed which makes the rear ride much smoother with airbags replacing the overloads to make higher and softer ride at the same time. I am very happy with handling and ride now, and I am extremely picky on those things.

I was exaggerating a bit of course, and I'm sure the original shocks are not helping matters, however it does not bounce up and down and rides quite nicely on the highway. Maybe I can find a bar for my generation van which is different from yours, throw some Bilsteins and air bags on and call it a day. Would have to be a decent improvement. Thanks to everyone who took the time to chime in on this.

[mkguitar]

Still happy, been piling on the miles, no complaints


cost/ benefit