cvh8601

Ok guys I want to get some expert opinions on something. I've got a vibration coming from what I think is the rear. I don't really feel it in the wheel differently than I do in the seat. i.e. the wheel has the vibe but its not rotating like if I had a warped rotor up front.

Edit: I noticed this vibration around the time that I hit a manhole cover really hard. Didn't notice immediately so it could be something else too but definitely after that event.

Having the wheels re-balanced had no effect (i watched the guy take the weights off, put the wheel on the balancer, and replace new weights in the same spots).

I played with jacking up the rear and seeing if I could determine whether a rotor was bent there, but it was very difficult to tell. All 4 wheels felt similar, some parts of the rotation were easier than others. Plus moving around the diff and axle obscured any feeling as well.

Question 1: Does this vibe well with a bent axle? Based on a bunch of other threads here it does with the exception that I'm not getting a brake squeak due to the rotor hitting the pad every time around due to the bend. Are there any other possibilities I'm missing? Im pretty sure I need a new trans mount (shifter moves a good amount when I get on it) - I didn't think that could vibrate the whole car.

Question 2: Is there any way to really check without taking the axle out and getting it on a lathe with a gage set up?

Any advice is appreciated.

FirstYrLS1Z

iTrader: (4)

jack the rear off the ground and support with jackstands. Start car and put in gear. A bent axle will show by the tire not spinning true(wobble).

jimmy92rs

What speed is the vibration at? Does it vib at all speeds?

mcamp001

iTrader: (1)

you may have a drive shaft out of balance.

cvh8601

I was swapping in my summer tires this morning and took the opportunity to get some video of the wheels spinning.

Neither looks perfect but the drive side looks worse to me. Would you guys recommend new axles with this level of runout?

metalmilitia606

iTrader: (8)

Looks fine to me. I think what you're seeing as wobble is just your eyes tricking you. If it were a wobble it would wobble through the center and not the sidewall like yours is doing. It's like when you ride your bike at night and look at the front tire and it looks like it is wobbling/moving backward. It's an optical illusion. Going with the pothole story I would suspect a bent rim over an axle.

jimmy92rs

Are your summer tires on a different set of rims? If so take it for a ride to see if it stills vibrates. If not then your other rims might have a bend in one of them. If it still vibs then I would check the drive line for looseness or excessive runout.

cvh8601

Yea the summers are on the stock rims, I had a different set of rims/tires on before. Should have taken a video with both.

Is it possible for a driveshaft that was previously in balance to become unbalanced? They aren't like wheels where weights can fly off... right?

jimmy92rs

They shouldn't because they are tack welded on but you never know. Check the u joints for looseness.

cgormanZ28

Do a road force variation test or have the tires rebalanced. Could be tires. Thats what was wrong with mine. I didn't road force mine correctly.