Increased Gear Whine
TECH Enthusiast
Joined: Dec 2009
Posts: 529
Likes: 0
As much as I'd hate to admit it, I've never checked pinion depth because I don't have the tool. I did obviously use a dial indicator to set up the lash and then some white lithium grease to check the pattern on the teeth afterwards.
I did read somewhere online, and then heard the same thing from a gear installer at a very reputable local shop that on our specific 10-bolt differentials that GM uses basically the exact same pinion shim on each car.
Its been a couple years since I set up my differential, and I can't for the life of me remember the exact number, but I'm pretty sure the pinion shim thickness was .029". This .029" shim apparently was used in nearly every single GM 10-bolt from '82 and on.
Its a couple years later and after many many long brake stands and 4500rpm clutch dumps on drag radials my gears are quiet as can be, so I guess I did something right lol
I did read somewhere online, and then heard the same thing from a gear installer at a very reputable local shop that on our specific 10-bolt differentials that GM uses basically the exact same pinion shim on each car.
Its been a couple years since I set up my differential, and I can't for the life of me remember the exact number, but I'm pretty sure the pinion shim thickness was .029". This .029" shim apparently was used in nearly every single GM 10-bolt from '82 and on.
Its a couple years later and after many many long brake stands and 4500rpm clutch dumps on drag radials my gears are quiet as can be, so I guess I did something right lol
just think, all it takes is one guy on the production line to have a bad day and you have a difference in tolerances, a couple thousandths is all it takes. a rearend housing/third member is actually a precision component.
ive done two 7.5 chevy gears before, and about six 8.8ford gears, the 8.8's seemed were closer than the two 7.5's but the gears were off from what the factory pinion shims were.. the dozen or so 9 inch fords i have messed with were all over the place but they're easier to mess with because you can set them up on the bench.
the 4:10 richmonds in my dodge ram were way off from what the factory pinion shim was, like .005 , i only have 50k miles on those, they make some noise at about 75mph, i think its more the richmond gears though.
