stunna p

iTrader: (4)

After my moser 9 install, and new shocks, and springs. Adj torque arm. From the rear, When cruising above70mph. My ws6 hums and has a distinct repeating noise. It sounds like hum......hum......hum...... hum...... and the faster I go, the louder it gets. At 80 mph, you cannot hear the radio that well....... so any ideas on where to start? Thanks stunna

ssvert99

iTrader: (26)

it's called "driveline droan". Most likely causes are from and inbalanced driveshaft, excessive ring and pinion runout, and driveline/pinion angle out of spec or improperly setup. The pinion on a 9" rearend is located lower from center than a 10 bolt so your trans crossmember may need shimmed to get the driveline angles setup properly along with the pinion angle... they work together and the two angles must be the same(but opposite)to cancel out vibes.

Bob@BruteSpeed

iTrader: (16)

Make sure the torque arm bracket is not rubbing the sheetmetal of the floor. By now you should be able to see rub spots if it has been rubbing. It is easy to take a pry bar and shove it up there and pry the floor over. There are generally two spots where rubbing will occur, and if it does rub, it makes the kind of harmonic sounds you are describing. For those reading this, the Moser fabricated rear (M9) does not encounter these problems, and the torque arm brackets are much smaller and the supplied torque arm follows the contours of the transmission tunnel. Bob