Aviator857

The rear of my car is siting uneven. The passenger side is about 1 inch higher than the driver. I put the car up on jack stands and checked the springs and they are indexed correctly.

From the spring perch on the axle to the upper mount there is .5 to 1 inch difference with jackstans under the axle as close to level as I could get it. The isolator is on both sides. It was hard to get a good point to measure.

Is this just spring sag or has the body gotten twisted. The front wheels are close to equal, and since the car badly needs an alignment I think it will be 100% equal after the alignment. The car has been siting alot and only gets driven occasonally. It has 210k miles and its the factory ws6 springs. It has subframe connectors and the car was sitting level when they were welded in several years ago.

Any advice on measuring or how to decide if its the springs or the body without buying new springs.

What should the distances be at different points on the rear suspension.

If it is the springs what are the best for factory height I don't want to go much lower than a 1/2 inch drop from factory.

tony_cogliandro

iTrader: (3)

every car can benefit from sfc's - jack it up - let the wheels hang and stretch the body a little - but on the sfc's and see if its even. if not - no harm - we all need them. if it is right you know you fixed a problem.
have you thought about going to a frame shop where they can dial in the height and even the body height and tell you if you have sub frame problems.
50.00 well spent.

JamesC

iTrader: (5)

There is no indexing on the rear springs. Ride height (which I've never been able to verify) is 27 1/2" from the ground the the fender lip.

JamesC

camarozz383

iTrader: (2)

these cars twist and there is a lot of them like it. mine is at least, so is my other camaro and TA buddies.

Aviator857

it already had sfc's I welded them in 3 years ago and it was sitting level then.

I did just have the fuel pump replaced so I am wondering possibly if they didn't get it back right.

Will a frame shop be able to dial it in if its worn springs, I know they cant fix the springs but can they measure the frame?

The body panels all still lign up and the t-tops sit right. The doors still shut and open correctly.

I wasn't sure if the springs on the rear index or not but I rotated them until they hit what felt like a notch.

I guess I could swap springs from side to side and see if the problem moves or changes.

Aviator857

I haven't got on the gas real hard and its the factory 305 so I don't think I have the torque or hp to tweak the frame with 2.73 gears..

I'll call a body shop tommorow and see if they can check it out for me.

SDIF

Your Rear Spring(s) is (are) not in the perch properly.

Jack up the car by the rear end center section.

Put jack stands on the chassis in front of the traing arms and let the car down on the stands. You need to have the rear end unloaded and dangiling

Take the rear tires off.

Look up into the spring perch and center the spring with a pry bar. I should go "pop"

Put tires back on lower the car with the jack on the rear end. It should be better.

I run into this problem frequently when swapping springs on the race car.

Aviator857

thanks I'll try that, they looked to be centered in the perch. I looked at it with and without the weight on the springs. I've got new bushings I bought a few years ago and never installed them so I may just go ahead and strip down the rear and put in the new bushings. As I put it together I will line everything up as I do it.

if it turns out to be the springs what is the best for factory height?

oil pan 4

iTrader: (1)

My boss put Moog OE springs on his V8 third gen several years ago.
It rode way too high. He said it would settle after a week. Then 3 weeks later on a monday it all of a sudden looked normal. He pulled the springs and took 5/8 of a coil off the front coils.
I replaced my springs about 2 years ago with 1-2 drop ebiach springs and it looked normal.

Aviator857

ok I swapped the springs side to side the problem remained. I doubled checked the springs and they are centered. I didn't swap the isolators but they looked to be about the same, the indentation in the isolator is why I thought the springs could use indexing.

Here are the measurments with the car sitting on a close to level cement slab, ata the buble on the the level is in the lines but to one side. These are from the ground to the fender lip.

Front Driver 27.5
Front Pass 27.5
Rear Driver 27.5
Rear Pass 28.5

The rear bushings are factory as are the springs, could the pan-hard bar or torque bar, or other suspension component be binding up? I guess if that was the case it wouldn't stay on one side as I drive it.

I want to get a FE alignment as I just replaced all the steering components but I don't think the alignment will be accurate if the suspension isn't setting right.

Could one of the shocks be the problem, it shouldn't as they will allow the rear to squat if you put your weight on either side of the car...
I can't imagine that if the frame was warped that 3 of 4 would not of been the same I would think the warpage would push one side down and one side up.

I put a jack under the LCA mount on the driver side. I jacked it up until I got an even measure across the rear, that was acheaved at 30 inches. I'm going to let it sit like that for a few days unless some one thinks it will cause a problem.

Like I said the body seams seem to be as closs as any thirdgen from side to side. I checked to make sure the springs were centered in the perch.

I guess this leaves me with taking it to a frame shop :-( but I guess I need to know before I put more money in parts.

Any suggestions would be helpful.

Aviator857

If it turns out to be a twisted frame. how would I re-inforce it to keep it from twisting again after I have it straightened? It already has bolt-in subframe connectors that I welded in after bolting them in. I don't want a roll cage in the car, If I wanted a 2 seater I would buy a vett.

Aviator857

Today at lunch I got to thinking the car had a flat front driver side tire while it was sitting for a few months with a dead fuel pump. This would of put some torque on the torque arm on the car as well as taken weight off the passenger side spring. It would of also put pressure on the sway bar on the rear. Im wondering if all this could have combined to cause the problem. with the DS front low facing the rear of the car the torque arm would be twisted clock wise from the rear of the torque arm. bring back up the front and the torque arm could cause what I am seeing... I think I'll have to check that tonight.

The flex the flat would cause on the body if it flexed would of been opposite I would think once the tire was pumped back up.

It will be a few weeks before I can get it to a body shop to check the frame.

Can I loosen the torque arm and put the car back down, I know I can't drive it like that but would that help prove/disprove my current theory?

PV9685

You can try disconnecting your swaybar enlinks and your Panhard rod to see if there is an issue such as binding. Is it possible that your sub frame connectors moved? i know that you mentioned bolted/welded... though if the weld broke and they moved /

Stephen

iTrader: (12)

If you tightened the LCA bolts while the axle was at full droop, that can "lock" the LCA into not moving & holding one side high.

Which would explain why 1 corner is high.

Loosen those 2 nuts on the LCA bolts, with the car sitting on the ground, roll the car a few feet (bolts in & the nuts on, but not tight), tighten the nuts back up & see what happens.

Aviator857

the sub frame connectors look like they have not moved, welds are not broken.

I removed the end links no effect.

I haven't un mounted the pan hard.

I will try that and the LCA trick. I did have the fuel pump replaced and I don't know what all they took off to do that...

PV9685

Yup, he's got a good point there with the bushings. I dunno if you need to roll the car a few feet, I'd guess pushing down/up a few times on the vehicle would cause it to move into place.

Other than that the only thing that could affect anything would be the shock but, you said it can move up/down so there's little likelyhood of something strange with that shock...

If the LCA bolts being loosened do nothing.... you have quite a strange situation on your hands

Aviator857

I didn't loosen the bolts, I checked and they haven't been taken off. I put it up on jack stands at the body lca mounts. Then slowly jacked up the rear and the bushings moved as freely as you would expect. I think I need to order new bolts before I try to break them loose as I don't think they have ever been removed off the car and the threads have some rust on them.

My garage floor in the work shop isn't quite level (just bought the house I need to get some thin set to level it out). BUt the problem exists even on a level floor.

I put the jack stands on the floor and put a level between them and that point is level. This is at the body LCA mounts. Then I jacked the car up on the front under the center of the K-member. Then I put a 2x6 under the car and shimed it so it was level. Measuring from the same bolt on the k-member body mount on either side on the front to the 2x6 I got between 1/4 and 1/8 of an inch difference with the ps being higher. Measuring at the rear finder lips I had about 1/8 of an inch difference with the ps being higher.

So there is some differences in the body, but not enough to account for 1 full inch difference at the fender wells on the suspension.

I hate to go this rout but I think I am left with taking it to a body/suspension shop and getting every thing checked.

I've thought about taking the ps isolator off as that is almost 1 inch it should level out the car but that is just a hack solution.

Aviator857

Thought if they didn't get the tank back centered could the weight of the fuel be the problem... Its got 3/4 of a full tank.... The filler neck isn't exactly where it was orginally, not bad.

gas weighs around 6 lbs per gallon.

1 gallon is 231 cubic inches

The car has a 14 gallon tank,
imensions: 33 X 23-3/8 X 11-3/8 inches

so lets say I have 11 gallons of gas that is a total of 66 lbs

if the tank is 1 inch off center assuming its level to the body that would be at the most 6 lbs of weight off center. for every 2.35 inches of width of tank it can have at the most 1 gallon of gas. So if its 1 inch off center it would 3 lbs light on one side and 3lbs heave on the other a moment of 6lbs. If the tank is tilted to the body the amount of fuel off center would be hard to calculate with out going into some serious math.

I may go and buy some $20 shocks and switch them out and see what that does, or swap them side to side as a final at home check.

tony_cogliandro

iTrader: (3)

keep us posted i am really anxious to see what the problem was.
aer the sfc in right? could they be off a bit?

Aviator857

the car was level when they were welded in. I did it with the car on its own suspension and we measured the car off the lift (drive on lift) to verify it was sitting level.

If I get it checked by a body shop and its off, I will grind off the welds and remove the sfc before getting it straightend. If I do this I will be going to the fully weld in ones Spohn sells.

I don't look forward to grinding off the welds, and only want to do if I have to.

camaro_guy24

I have a similar situation with my firebird except my problem lies in the front of the car. my pass side is about 1-1.5 inches lower than the drivers side. I thought that maybe my spring was broke but I changed the brakes tonight and didn't see where the spring was broke. Could the upper end of the spring be broke or can it be just a sagging spring? My camaro has the same problem as well.

Aviator857

I would avoid measuring the front off the fender lip since there is adjustment and movement in the front fender. On the rear its part of the the body so if its off its off.

If the front is uneven though I would look at the following.

As I've descovered it can be alot of suspension problems. On the front it can be worn springs. The front springs have to be indexed (search will turn up how to do this). Standard Front end Alignment can effect the front suspension if the struts are at drastically different angles then the front will be at different heights due to tire tilt.

Good luck this is driving me crazy.

Colt

Aviator857
I have the exact same problem that you do. The passenger rear is 1 inch heigher than the driver's side. I've noticed that it wasn't equal a while ago and today I decided to look into the problem. The car is an '89 Formula 350 with Eibach pro kit springs and about 73,000 mi on the body. I've owned the car since 1996 and I know this problem wasn't there all the time. I'm not sure exactly when it happened. Today I swapped the springs and checked the isolators and was unable to solve the problem. I truely believe it is twist in the frame. There can't be any other explanation. I'm not going to bother having a body shop fix it because now I have a full roll cage installed. I'll have to think about what I'm gonna do.

Tom

Colt

Well after looking at the problem some more, I have determined that it is indeed chassis twist. Try this...
Jack up the rear of the car at the underside of the differential, then
measure the distance from the bottom of the wheel lip, through the center of the wheel, to the bottom of the fender as seen in the picture.

When I did this both of my measurements were equal. This leads me to believe that the chassis is twisted. When you jack from the center of the differential it allows both sides to even out and self level. See what you get.

Aviator857

I took it to get the front end aligned and the stuts had play in them, so I replaced them and got it aligned. I also had the shop spec out the car. From the pinch welds to the alignment lift the measurments were correct (just about 1/5 lower all around) but you could see that it was still visabily uneven on the fender lips. The rear track is off 1/1000 of an inch but not too bad. The shop said that was well within typical for the car, Adjustable lca's would fix that and with an 20 year old GM 1/1000 is within tollarance in by book.

I got it off the lift and it was still off at the fender lip.

I took it for a drive and pushed it through some curves till the tires started squealing. Got home and looked at it and it was sitting level at the fender lips...

I don't know what the problem was but it seems to have fixed its self. Maybe the car just needed a good work out :-)

Thanks for all the advice -- to bad I don't have a conclusive answer but something must of been in a bind.

Colt

Hmm... I would be surprised if your problem is fixed completely. I don't understand how driving around aggressively on street tires fixed the problem. Do you know exactly what points the shop used to check the straightness of the chassis?

Aviator857

They measured the pench welds, I didn't watch them so I'm not sure the exact point. I doubt the problem is fixed if it was the chassis if the problem was in the suspension I think it may have lossened up. A body shop I know looked at it in the parking lot before it flattened out and they said if it was the body they didn't want to try to pull it unless I was ready to paint it incase one of the panels flexed when the chassis is pulled. I plan on working on getting the parts I want and when I get ready to paint it I will get the body shop to verify and pull the frame if needed.

PV9685

Well, if the LCA's weren't unbolted - my guess is that the car was sitting on a lift and one of the bushings physically turned from the twisting pressure since the car was raised. When the car was ont he ground it probably didn't have enough pressure to twist back to a normal position. Going around hard turns, the jerking-twist motion probably allowed it to twist back into a more suitable position. Just a guess.

So, it would have been a similar situation to if they were bolted back together when the vehicle was raised. Perhaps spray them with some silicone so that if they do twist again they will have some lube to move back.

IDK, I'm just taking a guess.

Well, good luck and I hope that you don't have any frame issues. i'm glad to hear that you got your wrinkle ironed out (essentially).

Fords88Bird

I was going to suggest measuring the actual quarter panels to see if they were equal in specs and also checking for any signs of replacement of that panel. Sometimes stamped replacement panels from different companies don't always match. Later.

Aviator857

to my knowledge and the records on the car its never been wrecked. It still had the factory paint when I bought it in 97. My over all guess is that it had something in a bind.

InfernalVortex

iTrader: (4)

I know this is a bit of an old thread... but I figured I'd share my experience with this.

My RS used to sit a full inch higher on the passenger side.

I swapped some Koni yellows and IROC springs on it... and even though the front of the car suddenly sat much higher, it was still higher on the passenger side than the driver's side. It was bad enough that i'd always take pictures from the driver's side because the car looked better from that angle.

Anyway, after about a year of sitting, I put it back together again. Each side now sits within a quarter inch of each other.

I think the problem was the LCA bushings. Because even though I changed my engine, transmission, and rear end, the only actual suspension change I made was switching to new tubular LCA's with new bushings.. So I think the LCA bushings were just old and binding.