Fitzy

I get a bad vibration from 55+mph and even worse in 5th-6th gear and it only started vibrating after a wavetrac and motive 4.30 gear install. Also, the whining is way worse than before when it was a trueTrac and 4.11's.

Could it be the pinion angle causing this? It has a brand new steel pst driveshaft in it also. Any help would be greatly appreciated.

Bob@BruteSpeed

iTrader: (16)

More than likely it is the pinion angle that is off, I would start there. Bob

LiT1_up

iTrader: (16)

Tremec has a great app that turns your smart phone into an angle finder. Get the app and follow the instructions, it help solve the issue I had with my 9". Get it for free at the google play store.

SStressin

iTrader: (5)

i have the same setup wave trac and motive 4.30s never had this vibration and i just started getting slight gear whine and im on decel in 6th gear other then that nothing. id check your pinion angle

Fitzy

Thanks guys. The car is at a performance shop right now and they're claiming there's too much play in the wavetrac. They've said pinion angle was spot on as well as gear backlash. It's hard to believe the wavetrac is shot with 200+/- miles on it and no real launches.

1 FMF

iTrader: (1)

my guess would be problem with one or more of the following
- pinion yoke runout
- carrier runout
- axle runout and balance
- differential balance.

pinion angle (ujoint phasing) is easily measurable and easily corrected.
after that it could be drive shaft balance, but balancing a drive shaft is not rocket science and a common procedure and you could have that checked.
but do the axle makers provide proof of quality control regarding those things... no. and when you dare question it the immediate response is something external either your pinion angle or your drive shaft balance. call a drive shaft maker and question them... they tell you go check your pinion yoke runout.

dailydriver

For his steel driveshaft, YES, but if one has an aluminum alloy shaft, then, IF it needs to be re-balanced, GOOD LUCK in finding a shop that would be willing, able and ready to weld any weights onto it.

Fitzy

It vibrated with the stock aluminum drive shaft and didn't change when I installed my PST steel shaft so Ive ruled out an unbalanced driveshaft. Bob at Brutespeed has been very helpful and I am sending the differential out to wavetrac for them to check it out.

Bob@BruteSpeed

iTrader: (16)

Thanks. You'll have to let me know what they tell you. Bob