Body roll?

[Rick L]

Recently I replaced many suspension parts including upper control arm (thrust arm) with 750 bushings, front sway bar links, tie rods, rear pitman arms, and rear sway bar links. But after the replacment, I noticed I have noticeable body roll... Before replacing suspension parts, my car felt very planted to the road with minimum body roll. What part of the suspension would create more body roll? Everything was tighten to correct torque spec.

[ArnZ!]

Normally worn out sway bar links and such cause more body roll as there is more play in those parts thus letting the body roll more then it should. Most of the time getting thicker sway bars reduce body roll.

[BigKriss]

i would say shocks first, springs second

[genphreak]

The only thing you've replaced that can affect that markedly is the pitman arms and the front bushes. Even when worn, the swaybarlinks don't have enojugh play to do more than rattle and twank. Check your tyre pressures first :)

[Rick L]

My shocks and springs are good (running Eibachs + Koni Sports adjustables). Weird thing is that it was much better before replacing these new suspension parts. Can the bushings on the new suspension parts be softer???

[Tiger]

Did you do alignment yet?

[Jehu]

What kind of Tires are you running?

I recently replaced Michelin Pilot Sport PS2's with Toyo Proxes 4 and notice unpleasant body flexing during fast cornering. For instance if you're just driving straight on a highway and turn the steering wheel back and forth you can easily get the body to flex.

The suspesion parts are all OK so I was looking at the Tires. The PS2's didn't so this. The turning was crisp and precise. I was guessing these Toyos being an "all season" tire were harder than the Michelins so they transfer the forces up to the bopdy where the Michelins gave more and the forces went out the tires which may be why they wear out so fast. Well less than 20,000 miles and I was seeing thread.

[Rick L]

Yes, did the alignment after all new suspension parts replaced.

It can't be the tires. They are the same tires as before (Yokohama S-Drive 235/45/17 fronts & 255/40/17 rears). And I checked tire pressure and they are good. I noticed the body roll only after replacing those suspension parts so it must be related to those parts. Don't get me wrong, it doesn't drive like a Buick or anything and still handles well but not like before.

[Tiger]

Recheck all your sway bar links... After I did mine, everything was super tight.

[genphreak]

Inspect the thrust arm bushings. If not Lemforder, they could already be bad. I refuse to use them and put up with the noise of poly ones as the fitment can't go wrong and the cheap arms all have weak bushings. Only other thing I think can do this would be your rear subframe mounts; maybe they chose to break at this most 'opportune' time. Hoping you find it quick...

[BennyM]

Inspect the thrust arm bushings. If not Lemforder, they could already be bad. I refuse to use them and put up with the noise of poly ones as the fitment can't go wrong and the cheap arms all have weak bushings. Only other thing I think can do this would be your rear subframe mounts; maybe they chose to break at this most 'opportune' time. Hoping you find it quick...

I think tightening up all those components might have transfered a lot of cornering force to older, weaker components like subframe and swaybar bushings. My first gut instinct was springs, though.

[Rick L]

These new suspension parts have less than 1,000 miles so I don't think anything could go bad this soon. Besides, I felt this right after replacing them.

I checked all suspension parts today. All looks good. Nothing loose and everything tight. No subframe issue or crack or bad bushings... Not sure what it can be. I guess I'll just live with it as it isn't bad and my car just hit 165k miles today so don't expect new car handling...

[BMWDriver]

Hm... I don't know these parts, but does the "adjustable" in "Koni Sports adjustable" have anything to do with it ? Can you stiffen the ride or do they just adjust to different models ? (i.e. e34/e31/e32/e36)

[Rustam]

Recently I replaced many suspension parts including upper control arm (thrust arm) with 750 bushings, front sway bar links, tie rods, rear pitman arms, and rear sway bar links. But after the replacment, I noticed I have noticeable body roll... Before replacing suspension parts, my car felt very planted to the road with minimum body roll. What part of the suspension would create more body roll? Everything was tighten to correct torque spec.

I guess you replaced everything at once, now there is a challenge finding the culprit...
You say you replaced the thrust arms with 750 bushings. When these were installed was the car preloaded? And I don't mean simply drop the car, but drop the car PLUS put the additional loading on the front seats (+rear seats?)... Was this done? The bushings at the thrust arms have a minor tendency to actually effect the roll making it smaller, if the car is preloaded properly. This is because once the preloading is off, the bushings actually tend to pull the car down. Not much enough to notice in straight driving but much enough to notice in turning where the effect of "turning the bushing more" creates a difference. Please retighten the bushings dropping the car properly if this was not done.
Mind you this part is the only of all replaced that can actually affect the roll, and its perception. The pitman arms are there to aid in inducing simultaneous rear wheel "toe in" and "positive camber" during body roll aiding in steering accuracy.

[Rick L]

I have the Koni adjustables. I tried turning it to full turn to stiff. I think there is less body roll but with a slightly harsher ride (or maybe it's in my head)... Currently, it is set to 1/2 turn (complete 360 turn to full stiff).


Hm... I don't know these parts, but does the "adjustable" in "Koni Sports adjustable" have anything to do with it ? Can you stiffen the ride or do they just adjust to different models ? (i.e. e34/e31/e32/e36)

[Rick L]

No, I haven't retightened the trust arms with the load. Maybe that's it... I'll give that a try. Is there enough room to do this with Rhino ramp? My car is also lowered ~1.4".

Thanks everyone for your replies.



I guess you replaced everything at once, now there is a challenge finding the culprit...
You say you replaced the thrust arms with 750 bushings. When these were installed was the car preloaded? And I don't mean simply drop the car, but drop the car PLUS put the additional loading on the front seats (+rear seats?)... Was this done? The bushings at the thrust arms have a minor tendency to actually effect the roll making it smaller, if the car is preloaded properly. This is because once the preloading is off, the bushings actually tend to pull the car down. Not much enough to notice in straight driving but much enough to notice in turning where the effect of "turning the bushing more" creates a difference. Please retighten the bushings dropping the car properly if this was not done.
Mind you this part is the only of all replaced that can actually affect the roll, and its perception. The pitman arms are there to aid in inducing simultaneous rear wheel "toe in" and "positive camber" during body roll aiding in steering accuracy.

[Robin-535im]

Hi Rick - sorry to hear... it's never fun to spend all that time and and money and end up feeling like it drives worse!

In my experience with the e34 - I've noticed that new suspension bushings feel "rubberier" but that wouldn't give you more roll.

Best guess is that the rear subframe (beercan) bushings tore while the subframe was being manipulated to get the new parts in. When they are bad it feels like your ass-end is a 1/2 second behind the front end when you turn, like the rear of the car is trying to steer the front... Not sure how easy it is to see damage on them but if they haven't been replaced I would look to them next.

HTH

- Robin

[Rustam]

No, I haven't retightened the trust arms with the load. Maybe that's it... I'll give that a try. Is there enough room to do this with Rhino ramp? My car is also lowered ~1.4".

Thanks everyone for your replies.

Having the lowered car on ramps with the load may simply not provide enough room to turn the torque wrench before switching the socket's position on the nut getting up to the torque. This is 12 point socket. My car is lowered too so I find simpler to note the position of the suspension before taking things apart so when time comes to tighten the thrust arm I simply bring up the steering arm to the level and tighten the arm then (and the lower control arm too). Have a couple of guys of approximately correct weight sit upfront having loosened the nuts on both upper and lower arms. Note the position of the suspension. Take the whee off, undo the steering knuckle from the strut, bring the arms to correct position, tighten from the side of the car. Hard way, but true.

[Rick L]

Hi Robin, Thanks for the information. Is #2 from diagram below the rear subframe bushing you are referring to? If so, I'm not sure how that can be checked visually without taking the subframe out. And that's one thing I don't want to do. :( I try retightening the trust arm first and see if that improves and go from there.

http://iccrents.com/ICC/Driver/139/rear.JPG




Hi Rick - sorry to hear... it's never fun to spend all that time and and money and end up feeling like it drives worse!

In my experience with the e34 - I've noticed that new suspension bushings feel "rubberier" but that wouldn't give you more roll.

Best guess is that the rear subframe (beercan) bushings tore while the subframe was being manipulated to get the new parts in. When they are bad it feels like your ass-end is a 1/2 second behind the front end when you turn, like the rear of the car is trying to steer the front... Not sure how easy it is to see damage on them but if they haven't been replaced I would look to them next.

HTH

- Robin

[Rick L]

I talked to the service manager at Firestone where I did my alignment and he told me to bring in my car and they will re-torque the thrust arm with load for free of charge. :)


Having the lowered car on ramps with the load may simply not provide enough room to turn the torque wrench before switching the socket's position on the nut getting up to the torque. This is 12 point socket. My car is lowered too so I find simpler to note the position of the suspension before taking things apart so when time comes to tighten the thrust arm I simply bring up the steering arm to the level and tighten the arm then (and the lower control arm too). Have a couple of guys of approximately correct weight sit upfront having loosened the nuts on both upper and lower arms. Note the position of the suspension. Take the whee off, undo the steering knuckle from the strut, bring the arms to correct position, tighten from the side of the car. Hard way, but true.

[Rustam]

I talked to the service manager at Firestone where I did my alignment and he told me to bring in my car and they will re-torque the thrust arm with load for free of charge. :)

not just the trusta armes but the lower control arms too. all 4(!) arms must be loosened and retorqued with loading. i pointed at this in one of my previous posts.

[Rick L]

I didn't replace the lower control arm as they looked good (no play, no cracks, or anything). Maybe I should have replaced them too. Firestone tech pointed out my pitman arm bushing is bad on driver's side. How does this happen?!? It's less than 2000 miles. Maybe defect from factory? Anyway, I had the upper control arm (thrust arm) retorqued. But feels the same. I was told the rear pitman can cause the roll so I'll replace them again but this time oem.


not just the trusta armes but the lower control arms too. all 4(!) arms must be loosened and retorqued with loading. i pointed at this in one of my previous posts.

[Robin-535im]

http://iccrents.com/ICC/Driver/139/rear.JPG

Yeah, that's the one. You can pull the cover off and look at it from the bottom, but I don't think it will be conclusive. If you remove the cover (#5, held on by 2 13mm bolts (#9) plus the keeper nut (#8) that holds the bushing in), and jack up the car, you can see if the subrame goes with it or if it pulls away.

Replacement is easy with a bushing puller, and it's not uncommon for them to need replacement. I think it's even on Bruno's site...

[Rick L]

Thanks Robin for the info. I'll take look at those bushings as well.


Yeah, that's the one. You can pull the cover off and look at it from the bottom, but I don't think it will be conclusive. If you remove the cover (#5, held on by 2 13mm bolts (#9) plus the keeper nut (#8) that holds the bushing in), and jack up the car, you can see if the subrame goes with it or if it pulls away.

Replacement is easy with a bushing puller, and it's not uncommon for them to need replacement. I think it's even on Bruno's site...

[Rustam]

I didn't replace the lower control arm as they looked good (no play, no cracks, or anything). Maybe I should have replaced them too. Firestone tech pointed out my pitman arm bushing is bad on driver's side. How does this happen?!? It's less than 2000 miles. Maybe defect from factory? Anyway, I had the upper control arm (thrust arm) retorqued. But feels the same. I was told the rear pitman can cause the roll so I'll replace them again but this time oem.

1 the fact that the lower control arms were not replaced does not mean they should not be retorqued. if you replaced the upper control arms all should be loosened and retorqued with preloading.

2 you were told that pitman arms affect body roll, did the person bother to explain how that is so?

how did the person determine that the pitman arm bushing was "bad"? the rubber collar over the ball bearing gets worn at the edge with time - in minds of some people reasonably that can be deemed as bad bushing. not enough...

[Rick L]

Actually, he pointed it out when I told him about my issue and what was replaced. Rubber boot popped out and the inner metal part doesn't seem to be sitting correctly. Maybe it just looks that way since the rubber boot is off. Regardless, I have new ones on the way. Good thing is that they are easy to change... :)


how did the person determine that the pitman arm bushing was "bad"? the rubber collar over the ball bearing gets worn at the edge with time - in minds of some people reasonably that can be deemed as bad bushing. not enough...

[Jeff N.]

Interesting. I agree with Robin's idea that the rear subframes are worth a look-see. I would think you'd feel more squirm / wander in the back than roll if they were bad but it' can't hurt to look.

I'm almost wondering you are getting more roll because you have a tighter setup than before. With new parts, alignment, etc the car is more hooked up and thus you are getting more lateral g's leading to more perceived roll. Alignment in particular can make a big difference in how connected the car is; just ask any autoxer how critical it is to handling.

For what it's worth, when I added the RD aftermarket sways to my car, it went from 'sort of flat in the corners' to 'very flat in the corners'. I thought they really complimented all the other suspension changes I had made - Dinan springs and shocks, +1 tire setup, front camber plates, new bushings, etc. You may be at that point....

Is the car "loose and squirmy" or is the car just rolling more? Squirmy suggests something's not aligned or assembled right. Roll just suggests you may have more grip. Changing the shock dampening shouldn't effect roll - the konis are single adjustable and so you're only adjusting rebound, not compression. In fact, tightening up the front shocks without corresponding changes in the back could make the car understeer more - likely something you don't want.

Here's my setup running at a local track....(before I retired her from track runs :D)

http://home.comcast.net/~jsnord/pics/pr_535.jpg

Jeff

[Russell]

I filled #2 subframe mounts/bushings with Windo-wlid urathane (or a similar name) a couple of years ago in search for a wandering problem. I thought they were allowing the rear end to "self steer" the car. Not sure it had any real effect on anything. IMO, just replace them. Been told they are a pain even with proper toolss.

I am still searching for the wandering solution. I am replacing my rear struts this week for the first time in 188,000 miles. This should help some. I am using "new to me" rear springs with only 60,000 miles on them Thanks to Rick L. We shall see.

[Rick L]

Thanks Jeff for the info. No, it's not "loose or squirmy". It just seemed to roll more. I noticed this on fast and abrupt turns only. Spirited driving... :D

I haven't had time to checkout the rear subframe bushings yet but will do so this weekend. But the roll (or deeping) feels like more like it's coming from the front end. Maybe RD sways are on the next list for replacement? ;)

Nice photo... :D



Is the car "loose and squirmy" or is the car just rolling more? Squirmy suggests something's not aligned or assembled right. Roll just suggests you may have more grip. Changing the shock dampening shouldn't effect roll - the konis are single adjustable and so you're only adjusting rebound, not compression. In fact, tightening up the front shocks without corresponding changes in the back could make the car understeer more - likely something you don't want.

Here's my setup running at a local track....(before I retired her from track runs :D)

Jeff

[Rick L]

Sure, anytime Russell. Did replacing the rear shocks fix your wandering problem?


I filled #2 subframe mounts/bushings with Windo-wlid urathane (or a similar name) a couple of years ago in search for a wandering problem. I thought they were allowing the rear end to "self steer" the car. Not sure it had any real effect on anything. IMO, just replace them. Been told they are a pain even with proper toolss.

I am still searching for the wandering solution. I am replacing my rear struts this week for the first time in 188,000 miles. This should help some. I am using "new to me" rear springs with only 60,000 miles on them Thanks to Rick L. We shall see.