[jocus]

I've noticed this past week quite a wobble while I am accelerating hard; particularly noticable in 2nd and 3rd around 4.5k rpm. I thought it might have been engine related; perhaps a persistent misfire or something, but after goofing off with it for a while, it feels most likely related to the wheels - perhaps axle, cv joint, or bearing related.

With the windows wide open, if I grab the window sill while accelerating between 3.5-4.5k rpm, usu around 40-60mph, I can really feel the whole front end wobbling. This is only while accelerating hard though. Under normal driving I have no signs of wheels being out of balance or vibration at any speed.

any ideas?

I'm about to do the local SVTOA event too tbtbhtbh!!!

 

[xhrylle]

check your tired, You might need a balancing or even a rotation. If that dosen't help try a wheel alignment

 

[metallicanick78]

yeah, 90 % of the time, a wobble is due to balence. if not that then alignment, but if it is the alignment then youll see some feathering or weird tire wear if its been doing it for a while.

 

[BornAgainFordOwner]

Since the wobble is load related, I'd start by looking at the CV joints. Out of balance wheels should wobble at a given speed whether you are accelerating or not, and misalignment won't usually cause a wobble.

 

[Obocecha]

Make sure and check your tire pressure as well.

 

[Blurvfocus]

Since this is only under acceleration, I'm leaning toward play somewhere, and/or excessive caster. I know for sure too much caster will make the steering wheel go into a dance (just like head shake on a bike, if you're familiar with that), and any little play gives it the slop to get started easily. Throw in the forces involved with accelerating the car, and there's no telling what can happen.

 

[turbovation]

Possibly one of your rims is bend..or maybe more than one.

 

[Scott_SVT]

wobble under acceleration, likeliest cause is the inner CV joints. You should check them by..

with car on ground, in gear, level surface, e-brake on... reach under and grab the inner CV joint (not the axle shaft, but the actual 'bulb' of the joint. THE INNER JOINT IS THE ONE ON THE TRANSAXLE END OF THE AXLE... rotate it back and forth, and push up and down. If you feel any play, or if you see the boot leaking or evidence of the grease leaking past the clamp, your joint is bad.

You can also get that type of problem from lowering the car, it causes the joints to slide in too far, and they don't rotate freely

 

[jocus]

thx. I crawled under there this evening, and it does appear that I have some play on the driver's side.

Also, my driver's side rotor has been giving me some vibration for a while as I've been meaning to get the fronts replaced.

Is it possible a warped rotor could have led to faster wearing of the CV joint?

 

[BornAgainFordOwner]

A warped rotor should only be felt as a pulsing brake pedal when the brakes are applied. I don't think that it would affect the dynamic balance of the axle/wheel combination, at least it didn't on my daughter's old Probe.

 

[Scott_SVT]

Do the axle first, and see if the other problem dissapears with it... you could be feeling the axle for both conditions.

 

[jocus]

That makes sense; just as the acceleration load introduces wobbling, so might the extra load while braking. thxxx.

 

[jocus]

The replaced my halfshaft, which I suspected has had a problem for a loooong time, but they did not replace the CV joint. Though the wobble has been greatly diminshed, but still exists quite perceptibly; only while accellerating hard around 45--55mph. I'm thinknig about getting an alignment and balance done before having it checked out again, but I will probably have to take it back regardless.

I must say that with the halfshaft replaced it feels like a totally new car. Shifts, turns, accelerating all feel much more responsive. I wonder what the old one looks like.

thxxx for the info