mattszm6

I am getting a bad vibration from 3k to roughly 4k rpms consistently. After 4k it tones down a bit but shows back up around 70 to 80 mph no matter what gear or rpms at that point. I have replaced u joints and tranny mount. Nothing changed. I have removed the tranny and only found a worn clutch disc. The flywheel barely has any hot spots. They are small to minimal. The PP looks good too. No bent fingers or worn badly. The TB is smooth as silk. I am going to replace all of that but the flywheel before i reinstall the tranny and also get the FW resurfaced too. After all of that i have found nothing that i know of that would cause such a bad vibration almost like a growling sound. Plz help!

timnfxr

Recommend that you get the new pressure plate and resurfaced flywheel balanced. An unbalanced pair can cause vibration.

Injuneer

Wouldn't a clutch or flywheel imbalance tie the vibrations into RPM, rather than MPH?

Does the car have the stock torque arm? An incorrect pinion angle can contribute to drivetrain vibrations. Another possibility is a bent trans output shaft.

timnfxr

Not referring to OP's current issue, but if the clutch components are being replaced/resurfaced, it's prudent to have them balanced.

mattszm6

Definitely in the plans too.

mattszm6

Yes it has the stock arm. After the clutch install i will be checking that as well. Any pointers with pinion angle?

Injuneer

If the stock arm isn't bent, and the front support bushing is healthy, the pinion angle is probably OK.

JakeRobb

Have you ruled out wheel/tire imbalance?