Bama99z

iTrader: (7)

I just replaced all bearings, seals, and axels in the rear. The right axel was damaged more that the left, so we replaced both axels with new Moser ones. Gear mesh looked exceptionally well after install. Backlash was reset to .007" Bearing preload all set. Everything looks the same as others that I have performed.

The car is a 6 speed. Ok here lies the problem. From 0~50 MPH everything is quiet as a mouse, once you get above say 50 MPH it sounds as if there is a little whine under load. Once you press in on the clutch or take it out of gear the sound goes away. This leads me to beleive that it is not in the way that I have the rear set up and its something else.

Has anyone else experienced this problem? If so what did you find to be your problem? Any thoughts would be greatly appreciated.

Thanks,
Eric

Bama99z

iTrader: (7)

Oh come on now I know that someone has experienced this.

DwDrummer

iTrader: (31)

Thanks for making the thread Eric! The whine sounds just like this video and quits when you let off the gas.

StreetGliderX

iTrader: (2)

Fixing to tear into mine I think. My car sounds like it has a set of super swappers on it. Goes wop wop wop wop. Quits on the coast and gets worse on the drive. Seems worse at slower speeds.....

DwDrummer

iTrader: (31)

For real! Would love to get rid of the whine!

96lt4c4

iTrader: (5)

Welcome to the world of 10 bolts in a late model F body Camaro... I am not saying you did anything wrong on the setup but these 10 bolts are very finicky. Changing all the bearings out with new ones may have changed the spot the gears were riding and broke in at. Here is what I would have done before tearing it down. Clean the housing and the gears really good with brake clean, then run a pattern, and check to see what the back lash is. Take pictures of the stock gear pattern. Take is all apart, change bearings, put it back together, check backlash, if its off form where it was shim the carrier to correct the lash, check the pattern, change pinion depth to get the correct pattern, match to the old one.

The stock GM gears run very tight back lash. As tight as .004 when they are new. You may tighten it up some and see what that does. The pinion depth should be very close, I am guessing you put the stock pinion shim back in?

The bad news is you may never get it to go away. Now the only thing you could do is swap the gears which almost all the aftermarket gears are going to make some noise.

If you are going to take it back down, spray the gears with some brake clean, paint the teeth and snap a few pictures of the pattern and post it up. The drive side wont show much but the coast should.

Bama99z

iTrader: (7)

The only thing that I didn't do was to take the before and after pictures. However the pinion depth measured out spot on when I reassembled. However the backlash upon disassembly measured almost .010" Which may be a little loose as the factory says the .005~.009 is acceptable with new gears. However since we only changed the bearings and used the old gears I decided to set it back up as close as I could to the original measurement that was taken. Taken in consideration that the old gears were being reinstalled. With all that said the wear pattern looked pretty good on both the coast and drive. I am going to recheck everything hopefully this weekend.

The worst thing about the whole thing is this is not my car, It's a friend's and something is wrong with it!!!

We've done several of these in the past and not had any problems what so ever until this one. I would of much rather of had a problem on my car rather than his.

If we have to install a new gear set I have heard that the Motive Gears seem to be the quietest. I've installed a few sets of these but none of the other manufactures, So any suggestions on the other manufactures would be greatly appreciated.

96lt4c4

iTrader: (5)

If I was going to put any aftermarket gear in it, it would only be the orange box performance motives. They are a good strong gear. They may even be some of the quietest gears out there other than the stock AAM gears. Without hearing how much noise it is making now in person I cant say if the Motives would quiet it down or not. I used to be real **** about gear noise, its just hard not to think that something is wrong when you hear the noise. 90% of the time the gears can be setup perfect and still make noise, just something you have to live with. Turn the radio up, make the exhaust louder...

This is a picture of the pattern I had on my 3.90 Motives in my 9 inch. They make a slight noise but its not bad at all.

1 FMF

iTrader: (1)

sounds like it has an italian set of gears, when you let off does it go dego dego dego ?

i have the same tone, 550 hz, on my new axle. it's a dana 60 with a 9.75" ring gear, 3.73 ratio. mine comes on at 60 mph and goes away at 70mph. did it when new something awful especially under light load and had a little noise on coast as well. had new gear set put in it and still does it but not quite as bad, and it only does it under power now. got a second opinion on the new gear set after about 800 miles on it and the guy said the wear pattern looks perfect, backlash was fine, and i believe he pinpointed the noise with electronic ears so it wasn't an axle bearing it was definitely gear noise. was told he could put another gear set in it but had no idea if it would fix anything because he can't find anything wrong with the current setup. so now i'm just running it and living with it.

when i do an oil change on it i may throw some limited slip additive in to see if it quiets it down. that's the only thing i can think of doing at this point. regarding the 7.625" gm 10-bolt, I inquired about getting my original one rebuilt last year and the shop said he had done a few of those and they came out noisy, spent time with gm techs on the phone about the problem and either came to the conclusion or was told that the noise is normal given the small size of the ring gear. whether that's true or not i don't know, i find it somewhat hard to believe because at least from 1998 to 2002 these cars came off the lot with quiet rear axles. ironically this guy also recommended i go with an aftermarket rear with a larger ring gear.