question to the rear end gurus
 

Hi folks!

sorry, I don't know the correct english notations...... but here is my problem:

I have a complete stock Camaro Z28 from 1999 with LS1 engine, A4 and a 2,73 rear end with Torsen Zexel inside!

during normal driving I hear no abnormal noise, but after crossing the 60 KPH line I here a loud whine from the rear end :(
If I accelerate more and more the whine goes louder and louder.
It whines during coasting at the same speed too...... putting the auto in neutral doesn't change anything...

I had read a lot about the F-Body rear end, but what the hell is this whine from 60KPH + ?
are the bearings in the diff. worn out?

Wheelbearings worn out?

I jacked up the rear and checked the wheels..... there is no play and no abnormal noise if I turn the wheel by hand!

Second problem:

during coasting below 30 KPH I can hear a loud rattle if I drive light turns, especial right turns. After giving little gas the noise disappears.... I think its normal for the Zexel, but in my new Camaro it's unusual loud.

And yes, I checked the oil in the rear end.... It was enough, so I changed it with Castrol 80W140 synth. plus a bottle of GM's LSD additive.
I mean the rear end is a little bit quieter.....but still loud if I compare it to my previus 4th gens with the same axle!


I hope my grammar is not too tremendous :D

thanks for help!!

Were you able to look at the tooth contact pattern? If so, how did it look? Do you know how much gear lash you have? Did the problem start out slowly and get progressively worse?

I bought the Camaro with this problem!

to check tooth contact pattern I have not enough experience - I know exact what you mean, but I never worked at the rear end.
To measure the backlash I need a gauge....

Do you think my problem with the whine is a consequence from wrong settings inside the axle?
Is it normal wear after 80.000 Miles?

thx

i have owned several f-body's and the first thing i did with anyone i owned was to go through the rear end and replace all the bearings and re-set them up


usually the pinion bearings are the first to go and they will give you a noise then when they get worse they take out the ring and pinion

with that kind of miles on it i would suggest replacing all the bearings and re-setting your ring and pinion