body lean adjustment
Thread Starter
Racer
Joined: Aug 2014
Posts: 287
Likes: 9
From: Toledo
body lean adjustment
Hello all, I just replaced my rear leaf spring in hopes to correct a body lean to the left. The original spring was splintering so i thought it was the culprit. Anyhow, after installing the new spring my car still sits 1" lower on the left side rear. Could I correct this by adjusting the castle nut that bolts through the spring? I know these nuts are basically going to have to stay in the there general location on the bolt due to the cotter pin. I was wondering if I threaded one nut up a couple/few turns and the other side down a couple/few turns that this would correct the difference? Any thoughts on this? I understand the front spring could play a role in this. I am more curious about the effects adjusting the castle nut.
Thanks
Chad
Year: 1995 C4 corvette
Thanks
Chad
Year: 1995 C4 corvette
Melting Slicks
Joined: Oct 2010
Posts: 3,030
Likes: 794
From: Tollesboro Kentucky
Where are you measuring from?The body panels aren't always equal on each side.Most recommend to measure from the jacking points.As far as the nuts go,yes,they will raise or lower the car.
Safety Car
Joined: Aug 2009
Posts: 3,752
Likes: 276
From: Melbourne, Victoria, Australia
Hi
The springs need to be fitted with the ID tag on the passenger side, the engine and gearbox are offset to one side a little.
Check the sway bar mounts are connected and bushes secure not loose, it may be your front spring that is causing the lean.
It is easy to adjust the rear suspension to compensate, get some new bolts that have more thread for adjustment use two nuts to lock the position. Adjust the left side clockwise half an inch further and take her for a drive for the suspension to settle, will be a trail and error process to get it just right.
However best to replace the front spring, it may just be the rubber mount has worn away on one side.
The springs need to be fitted with the ID tag on the passenger side, the engine and gearbox are offset to one side a little.
Check the sway bar mounts are connected and bushes secure not loose, it may be your front spring that is causing the lean.
It is easy to adjust the rear suspension to compensate, get some new bolts that have more thread for adjustment use two nuts to lock the position. Adjust the left side clockwise half an inch further and take her for a drive for the suspension to settle, will be a trail and error process to get it just right.
However best to replace the front spring, it may just be the rubber mount has worn away on one side.
Safety Car
Joined: Aug 2008
Posts: 4,344
Likes: 48
From: San Marcos CA
The best working theory I have heard is that the lean is batwing bushing deflection which causes a 3/8-1//2" drop on the driver side. You can get adjustable rear bolts and just crank up the torsion on that side. You may be affecting corner weights...or maybe not- depends on how you look at it- I feel that it is just going to offset the 200 lbs of driver that is plopping down in the car.
on mine I even tried flipping the spring around thinking one side fatigued over the years...nope- same ride height- it is the bushings and/or chassis tweak the best I can figure.
on mine I even tried flipping the spring around thinking one side fatigued over the years...nope- same ride height- it is the bushings and/or chassis tweak the best I can figure.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
If the rear spring bolts are original to the car, there is a cotter pin that is inserted thru the castle nut and into a hole that goes thru the bolt. This serves to hold the bolt where it belongs. There would be no adjustment of the nuts possible using the OEM bolt.
When you installed the new spring, did you put the shims back in the same position (left and right and top to bottom)? Are the rubber spring bushings the same height? Are they cracked and compressed? It can't hurt to get new ones.
What ever you do with bolts, a change in the location of the nut on the bolt can impact not only the ride height but also the rear alignment. Once you make any adjustments, drive the car for a good 20-30 miles and then you can get the rear alignment checked and adjusted if necessary.
If you go with new bolts, get ones that are 12" long. Longer bolts are needed to lower the rear of the car. You can use Nylok nuts on the new bolts. Take one of the old bolts with you as a sample. While the OEM bolts are metric, I think you can also use the equivalent SAE bolt size. Just make sure they are a Metric 10.9 or SAE Grade 8 bolt.
When you installed the new spring, did you put the shims back in the same position (left and right and top to bottom)? Are the rubber spring bushings the same height? Are they cracked and compressed? It can't hurt to get new ones.
What ever you do with bolts, a change in the location of the nut on the bolt can impact not only the ride height but also the rear alignment. Once you make any adjustments, drive the car for a good 20-30 miles and then you can get the rear alignment checked and adjusted if necessary.
If you go with new bolts, get ones that are 12" long. Longer bolts are needed to lower the rear of the car. You can use Nylok nuts on the new bolts. Take one of the old bolts with you as a sample. While the OEM bolts are metric, I think you can also use the equivalent SAE bolt size. Just make sure they are a Metric 10.9 or SAE Grade 8 bolt.
Race Director
Joined: Dec 2002
Posts: 13,348
Likes: 233
From: SCMR Rat Pack'r Charter Member..Great Bend KS
Get a set of the rear lowering bolts from MAM, CC, etc. Use them to adjust the ride height.
Ten years ago this subject came up, and many guys said you cannot adjust the sag out with the lowering bolts. Since the bolts don't cost much, I got a pair and tried it. It worked; my C4 has sat level ever since.
Ten years ago this subject came up, and many guys said you cannot adjust the sag out with the lowering bolts. Since the bolts don't cost much, I got a pair and tried it. It worked; my C4 has sat level ever since.
Thread Starter
Racer
Joined: Aug 2014
Posts: 287
Likes: 9
From: Toledo
Guys, I need some more in site to this. I purchased two different sets of longer bolts (260mm and the 290mm) in hopes to rid of this body lean. For some reason I can NOT get the left side to raise up enough to match the right side. Im back to the original bolt on the drivers side and the 260mm on the right side. The nut is basically 2" lower on the passenger side! I monkeyed with so combinations and still came up unsatisfied. For whatever reason its seems the left side will not raise. what gives here? Can some piece of the suspension be bound up? again I have a new spring and new shocks. I have not thoroughly inspected the front suspension but I when I changed the shocks I did not notice anything unusual. Same with rear. any help here would be greatly appreciated.
Thread Starter
Racer
Joined: Aug 2014
Posts: 287
Likes: 9
From: Toledo
so.. after researching a bit more I found the lean is common. I'm gonna look at unloading the sway bar and re-leveling. Does anyone know of a good place to get a bushing kit for the rear suspension?
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Be sure to also check the front.
Here is a post that may help if you do a search WVZR-1 has posted some great and technical information on this topic over the years.
Here is a post that may help if you do a search WVZR-1 has posted some great and technical information on this topic over the years.
The trim heights should be in the diagnostic sections of steering/suspension/wheels in the 3 section of the FSM. There are also frame dimensions from a "datum" in the 10 section of the manual and you can use the same reference points and just use those points on a level floor to establish the relative height.
The information you want should be in two charts in the 3 section diagnostics just before the wheel alignment section.
You shouldn't require differences of 1" on the rear bolts to trim the car. You will likely use the majority of the inch each side to lower the rear to the height you want and mentioned earlier when you installed the wheel/tire combination a couple weeks ago.
If you would like 10" bolts and want to give it a go tomorrow 10/18 I work tomorrow in Tyson's and I'll carry a pair of 10" bolts and nyloc nuts to work with me!!!
The information you want should be in two charts in the 3 section diagnostics just before the wheel alignment section.
You shouldn't require differences of 1" on the rear bolts to trim the car. You will likely use the majority of the inch each side to lower the rear to the height you want and mentioned earlier when you installed the wheel/tire combination a couple weeks ago.
If you would like 10" bolts and want to give it a go tomorrow 10/18 I work tomorrow in Tyson's and I'll carry a pair of 10" bolts and nyloc nuts to work with me!!!