High Speed Vibration Remedies?

[Pvt_D]

I am the proud owner of a 72 fastback. Right now when I go above about 65 or 70 I get a strong vibration/shaking up front to the point that it doesnt feel safe at all. The steering wheel will bounce around with the vibration too. Is this something that would be caused by things wearing out and if so what could it be? What kind of reasonably priced upgrades can I make to make the car more stable at high speed? I am currently deployed but when I get home I plan on building it up to 5-600hp and id like to not have to worry about that stuff. Also can my stock c4 handle that power? Is there any kind of chassis stiffening you would reccomend? Thanks and god bless

 

[j69302]

If it gets worse the faster it goes, check the wheel and tire balance, could also be a drive shaft.

You also want to take a look at the condition of your suspension bushings, ball joints, along with all the steering linkages. I'm not familiar with the power steering on 72 mustangs, but if its similar to earlier ones, the gear boxes can wear out, along with the power steering control valve which has a balljoint to direct the fluid flow, which even brand new properly adjusted one, can create a lot of slack in the steering wheel.

Also, don't leave something as simple as the front end alignment either, incorrect caster and toe can create stability issues at speed. And these incorrect adjustments can be cause by sloppy bushings.

A out of balance wheel can cause a sloppy steering linkage to do what your saying. You need to get under there and see the conditions of things.

Myself, on the other hand, after redoing my steering linkages, and still having a somewhat sloppy feeling, I ended up putting in a rack and pinion. Best money I ever spent on my car.


But, you need to take a look around under there and see what the conditions of all those things are. And keep in mind, vibrations from the rear of the car can be felt through the steering wheel.

 

[horse sence]

check the idler arm bushings they may be worn out ,has the car set for a while?
the tires may be flat sided or have a bubble , the rims may be bent we have that problem here with pot holes in the roads,could be wheel weights but bouncing as bad as you say i would suspect one of the other, the stearing box on a 72 has the power stearing controlls built into the box other than that it is bassicly the same as earlier years,just no ram, congrats on your score, not sure what motor you have but the transmition should be an fmx or c 6 if it is larger than a 302

 

[67rcks]

You are saying "right now". What did you change prior to that?

 

[SoCalCruising]

You are getting good replies. These things are always tough to pinpoint from our armchairs. My recommendation is to start with the easy stuff and work toward the tough stuff. This could be as simple as an old balance weight coming off the rim. That's worth checking. If they're all there, I'd check for obvious problems in the bushings, as described above, then move to removing the wheels/tires and taking them to a shop to have them checked for roundness and balance.

 

[NotMyStang]

Do you get any vibration when you slowly rev your engine while parked?

 

[bartl]

If you don't feel comfortable checking it, many big-box auto centers, like Sears, Midas, etc., will do a free front end inspection and give you an estimate. Doesn't mean you have to have the repairs done there.

 

[rbohm]

wheel balance is the first thing that comes to mind to check. if you recently put new tires on the car, and the problem started about 500 or so miles later, then what is likely happening is the tires have stopped squirming, and the balance has changed. its not as common as it used to be, but it still happens.

a wheel weight may have come off, or some mud has gotten stuck somewhere and is causing an out of balance issue.

if the tires are new, and they were balanced but the problem still persists, then consider having the tires trued. sometimes an out of round tire will cause the vibration, and once trued it goes away. again not the issue it was years ago, but it still happens.

if you recently put new brake drums of rotors on while doing a brake job, they may be out of balance.

these are the places i would start with.