lmatt

I have posted this before and thought maybe found the problem. Nope. I have a 90 fox 5.0 5spd car. 3.73 rear gears. It has a vibration at about 78-80 mph. Have put a vibration sensor from a Ford dealer where I work on it, and found that the most g's were coming from the axle housing. So, we re-built the rear end this past weekend. Different ring and pinion, new side gears, pinion bearings. The side gear splines were loose on the axles shaft splines. The new ones took about 50% of the play out. I know it will need new axles befor long. Could it have a bent axle at the splined end? Have check the axles on the flange with a dial indicator, no problem. Any ideas where or what this vibration could be?
We have swapped the wheels, driveshaft, ran it without the brake drums on. Still the same results. Please help with ANY info. Thanks alot guys.

MadMan@TheWheel

It could be a bent output shaft on the tranny.

lmatt

Went thru the tranny last winter. HAd the output shaft checked on a lathe. No problem. Thanks for the suggestion. Keep em coming.

MadMan@TheWheel

But you are having problems right now correct...Not last winter

lmatt

Same problem last winter that we have now. Has not changed with anything we have done.

Pony 5.0

Might check your u-joints. I had a similar vibration problem at the same speeds and it turned out to be them.

lmatt

Pony 5.0, did your shifter vibrate REALLY bad. Almost to the point it hurt to hold onto it??

mustangsneverdie

check the rubber grommets around the bolts at the crossmember to see if theyre missing mineare an it starts around 60 mph

bbbngowc

It's vibrating only at moderately high speeds? Harmonic Dampner perhaps? My car vibrates really badly at low rpms and the shifter as well. When I go to 50+ it smoothes out. Some told me, if my vibrations happens at high RPM then it would be my Harmonic Dampner/Balancer. Since mine has the shakes at low rpms it's probably my fan and clutch causing it. I'm replacing those next week.

bbbngowc