Whines on acceleration ??

trevorcrum said

Hello All,

I recently purchased a 74, 360 duster and the car whines under acceleration. It happens when I put my foot on the gas just a little bit, it will start whining, and then whenever I pull it off, it immediately stops. Coasting is quiet. It's actually hard to hear where it's coming from, but I'm assuming something in the rear end. It's a 727, with a 8 3/4 suregrip 3.91 gears. Under WOT it seems to go away.

Just wondering if this is "normal" for this type of setup, or there is something that I should look into.

Thoughts ?

Click to expand...

not normal at all
-- sounds like either the pinion bearings are worn -- pinion bearing preload not set correctly or the gear set was not set up correctly from the get go -- which means that is if this gear has been driven for many miles ,, you will not be able to correct the condition as the gears are worn in at this setting.
best bet is to pull the differential and find someone who knows what they are doing when it comes to differentials
--- have them check pinion preload and run a gear pattern check to confirm if the gears were set correctly---
if the pattern check is ok you should be able to rebuild the unit .