91MustangGt

Hey guys!

I've had this Issue for a long time now, basically since I got the car.....When ever I drive the car past 3000 RPM on ALL gears( Except 5th because I never really need my car to go that fast) it shakes like. The "Shaking" or "vibration" is felt on my transmission, driveshaft and motor. So if I have my hand on my shiftknob at all times I can feel my transmission vibrating hard past 3000 RPM, but like I've said before, the vibration is felt through out the entire drivetrain and motor.

What I've done to try and correct it is: I had my driveshaft rebuilt and it helped a tinny bit, I just bought Urathane motor mounts which will hopefully go on soon, possibly next week to see if I can fix it, the transmission has been rebuilt, its got less than a year on the rebuilt and its seen no real hard driving, havent gone to the track yet and I don't drive crazy..

So if anyone can help me Identify the problem or tell me what I need to do to fix is, I'd really appreciate it. The whole issue with it is making me want to stop driving my car completely and I really don't want that!

Thanks alot guys,

Ben

PRO50SC

Have you checked your harmonic balancer yet?

ikeybmg

so you had u-joints put in? hmm. harmonic balancer maybe.

91MustangGt

Hmmm...

You guys really think a Harmonic balancer can 'cause that much shaking? I forgot to mention also that at about 4700 RPM the shaking seems to stop, but I don't know if thats just because the sound of my engine drowns it out or what but I don't feel the severe vibration on my shiftknob when I get really close to about 5000 RPM.

Tims 88GT

if the HB is out of balance, it makes the crank dance

91MustangGt

Hey guys

If it is the Harmonic Balancer, what do I need to do to fix it?
Do I need to replace it ( if so can you guys suggest a good one) or can it be adjusted or fixed some how? Thanks...

Tims 88GT

if your not going to mod it a lot, a stock one is fine, but yes it needs replaced, start your car and look at the HB and see if it wobbles.

88blackCONvert

Did this start before or after you changed your U-joints? Check your bolts on your driveshaft again to make sure they are tight. I had them back out on me and had similar problems. Also look for the wobbly balancer.

88blackCONvert

If it is your balancer, check out summit racing. They have some good ones for descent prices.

runsrich

I had a friend that had the same problem and after he changed every thing he could think of he gave up and took it to a dealer and they replaced the fan and now its as smooth as a babys behind.If you don't want to spend the money on a fan until you know its bad just remove it (you may have to us a bunch of washers to keep the bolts from hitting the water pump) and take it for a short drive just watch the temp gauge.