Problems leveling my 240z

[Darren Mann]

I am having a problem with my suspension on my project car I can not figure out.  The Rear passenger side wheel is sitting 2-1/2" lower than the driver side.  My front passenger side is sitting 1" lower than the driver side.  I have replaced all control arm bushings, new struts and new springs, nothing has fixed the problem.  I am thinking I have something tweaked on the frame of the car at this point.  I have attached pictures of the rear tire clearance for a visual.  Any ideas would be appreciated.  If it is the frame, is it possible to fix the problem?

[DatsunZGuy]

This post might solve your problem:

 

http://www.zcar.com/forum/855418-post9.html

[Zed Head]

I am having a problem with my suspension on my project car I can not figure out.  The Rear passenger side wheel is sitting 2-1/2" lower than the driver side.  My front passenger side is sitting 1" lower than the driver side.  I have replaced all control arm bushings, new struts and new springs, nothing has fixed the problem.  I am thinking I have something tweaked on the frame of the car at this point.  I have attached pictures of the rear tire clearance for a visual.  Any ideas would be appreciated.  If it is the frame, is it possible to fix the problem?

Did the problem just appear out of nowhere, on a perfectly fine car?  Or after you did some work on it?  Is the problem that one side is high, or that one side is low?  Did you use factory stock replacements parts or aftermarket, like urethane?

 

Many possibilities.

[Darren Mann]

The problem was there before I did any work on the suspension.  The car has been sitting for the past 17 years.  I did use Energy urethane bushings.  The strut on that side was blown out when I disassembled everything so I thought I had found the problem.  After replacing the struts the problem was still there so I thought maybe the spring was bad causing the extra stress on the strut so I replaced that as well and still the problem.  I put Eibach coil over springs from motorsports.  The would think the link to the discussion on tightening control arms while jacked up would affect both sides not just one.

[Patcon]

Did you torque the suspension sitting on the ground or up in the air? Did you get all the spring in the correct location? You can check the car by putting the car up level on 4 jack stands. Measure the car to the floor at each corner to multiple places, the wheel arch the suspension mounts the frame rails, the rocker panels. If the frame is tweaked badly it will show up. Make sure none of the suspension arms are bent...

 

By the way nice deer...

[Darren Mann]

Thank you on the deer comment.;-)  Haven't seen one this year worthy of shooting so far.  Where would I position the jack stands to get it sitting level on them?  I did torque the control arms while in the air but I plan to redo this tomorrow and see.  Not real optimistic that would help since this problem was there before I put the new bushings in but I'm out of ideas. 

[Patcon]

Front frame rails and somewhere under the rear that's gonna be close to level. You can use pieces of plywood under the jackstands to shim the car close to level. Once the car is off the suspension you can measure the frame hard points to the floor.

 

On the deer note, I have seen several that were worth it but none I could get the scope on. Nice deer but small by Iowa standards...

[Darren Mann]

Loosened and retorqued control arm bushings under weight of the car and no change.  I lifted car off the ground with jacks and bumper was level, measured floor to upper rear fender and there was a 1" difference.  I did notice that someone had welded the bracket in 2 places that the control arm attached to near the gas tank as if they were trying to compensate for something.  It measured the same on both sides though.  It was a bit tougher to get that control arm bracket bolted up than the other side. 

[gundee]

The first thing I would do is with the car on the ground see if both front and rear

control arms are sitting at the same angle relative to each other.

[Zed Head]

Loosened and retorqued control arm bushings under weight of the car and no change.  I lifted car off the ground with jacks and bumper was level, measured floor to upper rear fender and there was a 1" difference.  I did notice that someone had welded the bracket in 2 places that the control arm attached to near the gas tank as if they were trying to compensate for something.  It measured the same on both sides though.  It was a bit tougher to get that control arm bracket bolted up than the other side. 

The urethane bushings are't really susceptible to when you tighten the brackets since the inner sleeve rotates, unlike the rubber factory bushings which are bonded to the sleeve.

 

Pictures of the welded area would help a lot.  I might guess that the car was in an accident of some kind.  Could be that the strut tube is bent and binding.  The control arm (transverse link in Nissan-speak) just rotates to where the strut and spring place it.  Most of the height is controlled by the vertical member.

 

One thing that can lift a side is the anti-roll bar.  Do you have one on your car?

 

Another possibility is that somebody replaced a strut assembly with a 280Z strut.  They're taller.  But you would have noticed when you replaced the insert/shock/damper/strut.

 

Could also be that they replaced the strut insulator, the big rubber piece on the top with the three studs sticking out, with a 280Z insulator.  The 280Z insulator is taller also.  Since you checked everything, I'm going to make that my #1.  It would be easy to miss, especially if you did one side at a time when you changed struts.

 

Apparently you bought a a car that has been sitting for 17 years?  The back story is always interesting for the viewers, if you share.

[DatsunZGuy]

I did notice that someone had welded the bracket in 2 places that the control arm attached to near the gas tank as if they were trying to compensate for something.

 

It's starting to sound like your frame was damaged at one time.  If I were in your situation, I'd take the car to a bodyshop that specializes in frame alignment.  That way, you aren't chasing your tail and and actually known what you're up against.  

[Zed Head]

Chasing your own tail is what this forum is all about.

 

It was mentioned that one control arm "bracket" was more difficult to get installed.  I'm not really sure what "bracket" means though.  Not sure why you would remove a bracket either.  But I do know that with the car on the ground I can loosen all of my bushings caps and the control arms won't move.  Loosening the caps might show if something is under stress.  The system is designed to move smoothly through its range of motion.

 

A picture with a description of what you saw would be a big help.

 

 

 It was a bit tougher to get that control arm bracket bolted up than the other side.