weires66

Howdy Folks! Happy almost Friday!
I could use a little advise. My 66 starts shakin at 65 mph. I have Cragar rims with the proper lug washers and spacers from Pep boys to keep the rims off the calipers.
I've replaced the lower control arms and a bunch of other front end stuff. I've got new tires, had the wheels balanced and aligned. The steering is really tight, but none of the work that two mechanics and Big-O tires did improved the issue.

Is there a type of mechanic that specializes in this kind of thing?

Thanks!

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19stang66

check the driveshaft u-joints. Get under the car and grab ahold of the driveshaft and try to move it back and forth/side to side. If it moves at all that means your u-joints have gone bad. Mine was doing the same thing as yours and both of the u-joints were shot. Replaced them and no more vibration. Nice car btw.

Cannonball888

If it shakes at 65 just go 70

weires66

funny thing is, i dont feel as much shaking/vibration at 70-75, but dont typically like to drive that high especially to resolve the shaking.
I'll check the u-joints for starters. What is the best type of mechanic to take this specific problem to? Should i go direct to Ford or a wheel/alignment place?

Soaring

I would take it to Ford.

P Zero

First, does it shake in the steering wheel? or Does it shake in the floorboard/seats? That will help narrow down where its coming from. ANd you say youve had a bunch of front end parts replaced, exactly what parts. Kinda need to know that info. Did they replace tierods? Worn tierods can and will cause a vibe, that would get worse around mild turns on the expressway.
-P.

Smothers

Could be a bent rim. I had some shaking going on at highway speeds even after I had everything balanced. Turned out one of my craiger ss was bent (don't recall how the tireshop determined that and why they didnt notice it when the wheels were balanced). Had to buy a new one, and the shaking went away.

btw could not tell the rim was bent by just looking at it.

Cannonball888

A bent wheel really is the most likely cause. A tire shop can easily tell by moving stationary pointer close to the rim while it's rotating. If it's even slightly warped you can see the rim moving in and out.

Soaring

It could be 500 different things. Take it to Ford......

ebluekeys

If you search on "high speed vibration" you'll find my original thread - looking for the SAME problem. Tonight I'm changing the rear outside wheel bearings.

I've already:
1) tried different rims/tires
2)replaced both driveshaft U-joints
3)replaced transmission rear isolation mount
4) replaced output yoke bushing
5)replaced inner differential bearings
6)Got a GOOD 4 wheel alignment
7)rebalanced driveshaft
8)checked axles for straightness
9) checked "runout" of all 4 tires
10)checked engine mounts.

Only thing I had left was the outside rear bearings, which are "sealed" units.

A few things to do to help isolate the problem:
Try to figure out the "frequency" of the vibration. If it's roughly 3 to 4 times the wheel rotation speed, it's driveline related (U-joints or transmission)
If it's at the wheel rotating speed, it's tires, rims, drums, or wobbly (bent) spindles/axles.
Jack it up and run it up to speed while you look for obvious vibration. This didn't help me- it didn't show up unless the car was on the road...

Mine starts at 58 and gets worse the faster you go. Bad enough to blur the mirrors.

Good luck - I'll let you know if the bearings helped mine...