so...after the gear swap...all seems good....very very minimal whine while normal driving....type of whine you can only hear if the windows are up and you are dead quiet and really listening for it..

anyways when i hit around 100....the rear starts vibrating pretty bad.....wtf??? BZZZZZZZ sound...

these are used gears by the way....GM OEM ....034 pinion shim....backlash is set at .008

i turned the drive shaft around 180 degrees....didnt help..

heh

 

what kind of gears , or i mean ratio. i changed to 4.10s and it vibrated a little more casue the rear is spinning so fast . It could be a bad u joint, the driveshaft could need to be balanced. change the u joint and then go from there.

 

3.73...gm oem.

shortly after i posted this i ripped the rear back off...tok an hour...

im assuming the pinion is too close to the ring.....

i need a daily driver so bad....THIS is my daily driver...and its never togather for more than a week before i take something off and modify it....making it yet more unreliable.....

yesterday i pinned the heads....today.....ripped the rear back off....

once i get this car running good again....m selling it....SO SO SO many mods...i feel sorry for the unsuspecting teenager who will buy it....itll be totaled in a week tops....heh especially if he has driven a rs before....then hops into a 300 hp sleeper and has no clue its packing muscle....poor kid...

 

I would suggest having the driveshaft checked.... I had a vibration I couldn't find and it turned out to be my stock driveshaft. I swapped in a new aluminum unit and it works great. BTW, the factory steel unit is only rated for 119 mph.... I had mine over 150 a couple of times..... Just a thought......

 

well this only started AFTER the gear swap

i looked at the gears...they look fine....cept for the inside of one tooth....prolly be ok if i grind it down some... --pinion tooth--

about a 2 MM spot looks chipped....damn used gears.....it looked that way before i put them in...just looks a wee bit worse now though....

i still say the vibration was from the gears.....it didnt do it before the gears...it does it after the gears.....chances are....its the gears..

the bearings are brand new...they look good....

there wasnt much metal at all on the magnent on the diff cover....i was suprised about that.....after i put 200 miles on brand new bearings and used gears....i figured there would be much more metal than that.....

 

I would have your driveshaft checked as well. It is now also spinning at a higher rate and we all know that is a common problem with stock steel shafts at higher speeds. So any previous vibrations you had will now be felt at lower speeds.

 

I have the same thing, have bene working on fixing it for over a year.

I replaced the driveshaft with a custom balanced racing one, no help.

I believe the problem is pinion angle. At least, that is my problem, yours might be entirely different.