Ken S

Back in June, I trashed my stock 10 bolt in my 99 Z28 on the street.. two bolts came off the stock torsen diff and got caught between the housing and ring gear, causing the rear to lock up, then crack the housing. Since then I got it replaced with another 10 bolt and a new and awesome T2R diff.

I noticed about 45-55 mph I had this whine on accel. it disappears.. then comes back with a vengence at around 90-100 mph.

So I got a new 3.73 ring and pinion replaced, with the rebuild kit with the bearings and shims and all that from SLP... The shop installed it and it feels fine.. except the whine is now on accel and deccel at 40-50 mph. (with the speedo corrected) I haven't gone above 70 mph since so I'm not sure if it comes back again in higher speeds.

The shop I took it to has tons of experience (hell, their name is Frame and Axle) with all sorts of cars and racecars, so I'd think they know how to setup gears properly.. I'm going to go back and ask em about it..

Bit I'm thinking, perhaps when I trashed my 10 bolt, I might have damaged the driveshaft and the u joints with it? That could cause some kinda resonance/whine at certain mph.. Especially when I got the gears and bearings replaced with the kit from SLP.. Also, the resonance range dropped about 5 mph after I did the gears, which matches with the gear change and the driveshaft speed relation.....

What do you guys think?

Since this is a street car with no future major power mods, that does AutoX and will be doing some roadcourse lapping times, I'm thinking with getting the 1LE aluminum driveshaft replacement PN# 12564004. What other stuff do I need to get (like the u joints or what?)

onefastgta

A whine on decelaration isn't anything to be worried about. Mine whine around 45 mph no matter what. After you beat on it, the crush sleeve gives a little and the ring gear/pinion gear tightness loosens up a bit. Everybody I know around hear has a rear end that whines slightly after running it at the dragstrip for a while.

Ken S

yea thats what I hear, although it happens on accel too, especialyl light part throttle when maintaing speed.


I kidna kinda live with it, but if at 100 mph when it comes back again (if its still there, haven't brought it to that speed since the ring and pinion and bearing changes, but I bet it is) it was REALLY disconcerning, cause it was really loud and distracting, like starting to seriously compete with my loudmouth exhaust! That can't be right! Its not very impressive or confidence building when you hit 100 mph and suddenly it sounds like the rear is going to break apart with that deafining whine/moan like a siren..


Before all this stock, it was whisper quite thruout every mph imaginable.. and it was beat on too.


So just living with it is not acceptable.. I guess we'll see what the shop comes up with.. Else I'll consider trading this car in for a new GTO or used Vette.. Best part is, the $ i can get for this car would probably drop because of "excessive rear end noise" at 40-50 mph.. Its a pity cause besides that, I really really like this car.

chpmnsws6

12bolt or 9 inch rear would solve all....... or a good 10 bolt someone took out when they put in a 10bolt

Ken S

new ring and pinion and bearings again... fixed the problem..

now I have to go thru the headache of getting SLP to refund my money back for the ring and pinion