Vehicle Ride Height

[JThomas]

My 1991 ZR-1 is currently 1/2 lower in the left rear corner than the right rear of the car. The car has 119,000 miles, but all suspension bushings, etc. seem to be in good shape.

Is there an adjustment in the suspension system that I could make, to raise the left rear corner of the car? Or should I consider replacing the spring? Is there any explanation as to why the car would be lower in the left rear corner as oppose to the other? (My thoughts would be either excessive weight on the left side of the car, or maybe because there is always a driver and not necessarily a passenger, leading to wear, or launches where load is displaced to the left rear?)

I'm the second owner of the car and it has been a project for a year now, but seeing the car "tilted" is really starting to bother me.

Suggestions?

[BigIke]

C4's do that. I put a loner bolt in the right rear, made it better.

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[RussMcB]

C4's do that. I put a longer bolt in the right rear, made it better. Same here. I did a bit of measuring, couldn't find an obvious reason for it. I bought the rear lowering kit (longer bolts). I considered shims between the spring and the chassis but didn't want to screw it up. Plus, I'v since seen plenty C4 owners say to not worry about it. It's a challenge making ride height adjustments on one rear side because the single transverse
spring is bolted to the chassis in the middle of the car.

You can always convert to coil-overs. :-)

[WVZR-1]

It sounds as if you're trying to measure from ground to quarter panel lip though the wheel center-line. Not done that way.

Use the trim height dimensions in the 3 section of the FSM. If you've significant issues with those dimensions you go further for diagnostics.

[JThomas]

Thanks for the information.

[Hib Halverson]

An unfortunate problem during the C4 years was sometimes uneven distances between body parts and tires.

It was said earlier that the only proper way to measure trim height is per the FSM which does not index body part position in space to trim height. I'd do that, first, to see if you really have a problem with trim height or if the problem is how the body sits on the chassis structure.

If there is a problem with suspension, that needs to be addressed with repair of either spring, control arm, control arm shafts, bushings or frame sections near suspension mountings.

If the problem is with body you may or may not be able to fix that.

Lastly, using one longer/shorter rear spring bolt may make the car look right but, if there was no preexisting problem with the chassis, you have created one by having different length rear spring bolts.

[JThomas]

Got it, thanks Hib.

[Starman]

I fought with this for years and finally figured out that I screwed the car up when I rebushed the rear suspension and torqued the bolts in droop. That causes the strut rods to bind. You might try loosening the bolts at both ends (1 is camber adjuster) and retorque to proper values. You will need a way to jack the car when you do this. Then the car should be very adjustable with the spring bolts. It should not take much of an adjustment for cosmetic perfection. As previously stated correct ride height is measured from the frame.


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[S.hafsmo]

Height adjustable suspensions should, if possible, be adjusted with the vehicle standing on 4 individual scales to ensure correct weight distribution. Ride height is not just cosmetic.

http://www.turnology.com/wp-content/blogs.dir/1/files/2015/02/lotus-corner-balance.jpg

Corner balancing (http://www.turnology.com/features/corner-balancing-is-a-lot-more-important-than-you-think/)

Edit: I am aware you're not running coils, just intended to mention other effects of uneven ride height.