Serious vibations! Help!

[LGDBenzo]

I had my car lowered three weeks ago, all went well. I did not get it aligned immediately because I wanted the suspension to settle first. When I first drove the car all was fine no vibrations, at any speed. Then a week later I start to notice a slight vibration through the whole car but only when i took my foot off the gas and the car was coasting ( at arounf 65mph).

As it got worse i figured it was time to get it aligned. Took it to the dealer paid $322 bucks got it done. Problem still persist. There is no signs of wear on the tires I am using stock shock absorbers. The vibration is severe now.

Surprisingly, according to the data sheet from the dealer the before and after alignment numbers are not that different from each other and in some cases it's it's farther afield from the target data.

Has anyone had this problem after lowering their car? Any ideas as to what this might be?

Thanks in advance for your feed back.

[1SIKBNZ]

dude im having the same problem! interested in peoples thoughts on this! thanks in advance!

[Denlasoul]

To check the obvious, are you wheels/tires balanced? Did you do anything to the suspension in the week you let it settle?

Secondly, I would take a look at the suspension components itself. Who installed the springs? Check each compneont to see if anything is loose. Also inspect the bushings (specifically the LCA) as they wear over. Also, check the upper control arms.

Do you have access to a mechanic or lift?

[LGDBenzo]

Wheels and tires are balanced (they are fairly new items.)
I installed the springs myself, they were done correctly, all bolts were tightened to the correct torque. Nothing was done to the suspension in the week that I let it settle other than normal driving.

I am thinking it's the toe adjustments, only because it accurs when the gemetry of the suspension changes during the transition from acceleration to coasting.
It definately has that coarse feeling of the tires scrubbing from excessive toe. ( i could be wrong)

I am going to fit the old stock wheels on the car tomorrow and see if it happens with those.

Just a thought. Would the shock absorber bolts need re-tightening after the spring settles?

I'll re-check all the componets and re-tighten if needed tomorrow. Thanks.

Any other thoughts?

[Denlasoul]

Originally posted by LGDBenzo
Just a thought. Would the shock absorber bolts need re-tightening after the spring settles?
Not sure, but worth looking into.

How much did you lower your car? I would think anything less than 2 inches would still be ok (in terms of camber,caster, toe)

[LGDBenzo]

The springs didn't lower the car that radically I would say 1.25inch, about two finger spaces between fender and wheel (fender gap), that's why i wasn't too concern about driving the car without re-alignment.

I am suspecting from the way the problem gradually presented itself, over a period of a few weeks, that it's the results of the tire begining to wear badly. Hopefully with the re-alignment done and a tire rotation it will correct itself... hopefully.

I've heard at least one instant of Kumho tires causing vibrations on this forum, I wonder if this has anything to do with it.

1sikbnz, what tires are you running?

[1SIKBNZ]

im running general, 225/35/19, brand new. i had th eproblem starting to occur before the tire change (change was about 3 weeks ago) the old tires were badly worn and i thought new tires would correct it but after new tires, balance, and alignment the problem persists which leads me to believe it could lay more in structual parts of the front suspension, bushings etc etc... id really like to figure it out and get it resolved though

[LGDBenzo]

Denlasoul, you were on the right track. Problem solved. One of my wheels were loose, more specifically the right rear wheel. It would wobble and shake when the weight of the car shifted to the front when i let off the gas.

Three bolts where missing and one had sheared off, the wheel was hanging on by two bolts. Thank God I wasn't on the highway. Apparently they weren't torqued properly after the suspension job and worked themselves loose over a period of a couple of weeks

I replaced the bolts re-torque all the wheels and the car is as smooth as a baby's ass now.

Thanks for all the feedback guys

[Denlasoul]

Awesome! Pretty easy fix, but sux that it happened. Good thing you werent on the highway or anything because loosing a wheel would have been bad. I blew out a tire at 60mph, couldnt imagine losing a wheel at 60mph.

[NEA-4311]

Jesus... Hey 1SIKBNZ CHECK your bolts too man... NOW!!! GO !