Car feels as if it sways from the rear, HELP?
 

Let me get started with the car facts. Bear with me please, I'm not suspension savvy and really have no clue what I'm looking for here.

1) My car was taken to Monterrey, Mexico (current city I live in) about 8 months ago. I live in a certain area where the roads are not the typical torn up Mexican roads we all know off, but they are also not decent like the ones State-side.

2) I've clocked about 3k miles on Mexican roads, car is at 63,005 as it sits today.

3) Before taking the car down I took off my coilovers and re-installed my stock suspension which, was taken off at 12k miles and paired it with Eibach springs (forgot which one, but it was a small drop)...a slammed Z would not survive the speed bumps over there.

4) About a month ago I started feeling something loose...so I started paying attention. A few miles later I came to the conclusion...every time I hit unevenness on the road, whether it be a slight change in pavements, small bumps, etc...the rear feels as if it sways from side to side slightly. I figured...maybe a bolt of some sort has come loose since the car has to deal with shittier roads now. Stupid me took it to the "best" suspension shop in Monterrey and lets just say it was the first 370z they had ever touched....end product was no improvement on the sway, if anything got worse.

5) After that shop experience I took it to Nissan, long story short, they denied work on my Z...the head mechanic wanted to blame it on my rims because they sat flush with the fenders, "and if you look at that Nissan Versa with the rims tucking, that is how rims are supposed to fit, your car has the wrong size wheel"...quoting him.

6) Came back to Texas, took the car to get an alignment to a guy I have taken my cars for the past 10+yrs, was corrected (mentioned Toe was off bad) but car still felt loose on the rear. Asked friends and nobody really has an idea of wtf it is....so I took it Nissan (have a good relationship with them).

7) 1st visit (w/SSR wheels): Nissan says after full suspension inspection, it is probably my tires (Birdgestone Potenza S-04's) and their asymmetrical tread pattern = issue not solved. So I decide to slap the stock wheels and tires to test their theory....same problem.

2nd visit (w/stock wheels/tires): they said it was my alignment now, which they corrected aaaaaand car STILL feels as if it sways.


I've looked online and "bushings" keep coming up a lot...any opinions/idea/experiences would be GREATLY appreciated!

Anybody? 100+ views...come on guys, help a fellow Z member out.

Do you have aftermarket toe bolts ? Arms?

dampers shot, alignment.

Could you have lost a bolt on the swaybar? Maybe lost a bolt on one of the two endlinks. If that happened the rear would feel as though it's rolling through the turns. Just a random idea. Best of luck and let us know what it was.

Check the rear shocks maybe one is blown or like it has been mentioned something is loose.

You could probably reinstall your coilovers and see IF that resolves it.

Yeah I would start with checking out the endlinks. Its not that I really think its that but Al you have to do to check is jack up the rear and it went cost you anything.

I have SPC rear camber kit + toe bolt....funny you mention this. When I first installed this kit (no toe bolt) with my coilovers at that time, I felt this similar wobble....went back to get the SPC toe bolts installed and problem was basically fixed.

Doing the bounce test should help me find a shot damper...correct?

Thanks!

I did the "bounce test" and IMO they seem fine....any other way I can check them? I would reinstall the coils but they are long gone :/

Did a quick search on endlinks and worn out endlinks seem to make some sort of popping noise.....haven't head any noises like that. What exactly would I be looking at once lifting the car?



Thank you for the responses...:tiphat:

Look at the top of your shocks. Where the shaft goes into the shock body. See if that area looks wet with oil. If so, the seal as gone bad, and the gas is leaking/has leaked out. Once the seal is bad. It will also pump the oil in the shock out.

Since you don't mention any noises, I'm guessing it's something "soft" that has deteriorated. I'd first look at the bushings of everything connected to the rear end - if they are 6-7 years old, they have probably shrunk a bit and gotten hard.

If all the bushings are OK, I'd next look for parts that are not properly assembled/adjusted or may be flexing under load.

not sure about bounce test you mentioned, op. raise the car and check for leaks.
and be sure to get the car aligned.

When was the last time you had the alignment done?
When I went to the S-04's this summer from the factory tires the rear felt like it was all over the place, thought I made a mistake buying the S-04's. After the shop aligned the car and took out some negative camber in the rear, the car felt normal again. I would also take a hard look at the shocks and the sway bar links as suggested, You might even want to pop them out and check them, yes its more work, but sometimes shocks develop a wear point were it travels. Had that happen with a set of Koni's the rear felt squirrelly, the bounce test all felt normal. after replacing them the car rode normal again.