I've got a knocking/vibration through the shifter of my '90 5.0 (pretty much stock). I've had it for months and it's driving me nuts trying to track it down. So far I have changed the following with no difference: - Replaced driveshaft - Replaced u-joints - New tires all around (balanced too) - New rebuilt T5 transmission - New pilot and throwout bearing (although I still have the knocking when the car is in neutral and sitting still, clutch out, that is indicative of a bad throwout bearing) The knocking/vibration is audible from the transmission/bellhousing area and is noticeable at the following times. - First or second gear, generally at or under 3k RPM (above that engine/exhaust drown it out) - Most noticeable when engine braking (ie: letting off of gas and coasting) The noise goes away completely when the clutch is pushed in. It's not RPM dependant, so harmonic balancer doesn't make sense. I hear some growling from the rear end and I'm guessing maybe this is the axle bearings. Would the axle bearings cause this vibration/noise? Should I pull the transmission back off and replace the throwout bearing, clutch fork and clutch cable? What else should I check?