djm_e22

Alright 2 or 3 years ago I installed a Moser 9" rear end. I went from 3.73 gears to 4.22 gears. I hope I remember correctly by saying the vibration started after that. It starts vibrating at 65mph or so and higher. I have the stock steel driveshaft. I have heard numerous people saying going to real low gears can cause it and that you need to change driveshafts. I've also heard that you just need a high speed balance done to your driveshaft. Could it be something else? Keep in mind I do have a frame mounted torque arm as well. Which I know will cause me to feel some vibrations but why just above a certain mph. Also will a Denny's nitrous driveshaft get rid of this? Does anyone know what is causing this. Thank you sooooooo much for any help.

wrd1972

Its the DS.
Guarantee it. Get yours rebalanced by PST or Strange or buy a new one.

LearJet

I second that, I got a Denny's shaft and it is smooth as silk.