I've had the 9 bolt center section ( cones) rebuilt before...it will leave a pair of streaks up the driveway.....BUT when i go to open track days, it will spin what ever tire is on the inside of the corner......this happens when i'm moving along anywhere from 40 mph to 90.....i come out of a corner and step into it and one of em lites up and i have to back pedal....is there a different type of center section that could be installed in this housing that wouldn't do this? i also drive it on the street so they can't be locked all the time......any help would be appreciated. Thanks Pat

 

There is a very expensive German built differetnial for the 9 bolt, but that's it. There is a spring kit for the '04 to '06 GTO that should fit in the 9 bolt differential that might help. The GTO differential is almost exactly the same as the 2 series 9 bolt differential. They make a Truetrac for the GTO, but it wouldn't work in the 9 bolt unless you had 2.77 gears.

 

how much do we think the german diff cost? it may still be cheeaper to get one of those rather than another rear end for the car......i may look into a set of 2.77's..........to use the truetrac....i like the 9 bolt since it looks allot lighter than other units.........Can anybody think of anything else that might work in here?

 

The German diff is around $900 to $1000. Try this first. Drain the oil and use regular 80W90 and no additive. The additive makes them slip easier. Don't put the additive in it and it will lock up better.

 

well the oil trick is certainly affordable for a try.........i won't have the car back out to the track till spring though............

 

I was thinking about this and I guess Im still shocked its not working correctly.. I know its a small diff but with stock tire sizes I would think on a turn you should be getting loose rather than one tire spinning.

were they new cones? machined and shimmed? <--- if so how tight was it shimmed? mine is so solid it amazes me it is smooth in turns

 

i had the diff rebuilt at a guys' shop in NJ.....can't remember who it was now.....it was done about two or three years ago.....the car gets less than 1000 miles a year on it.....i rember sending him a bunch of new parts that i had gathered from e-bay....i know that the car is not getting loose on the corners as the whole back end would start swinging around on me......instead the rpm's go way up while the car stays going striaght......i let offr the gas and it hooks up again......

 

Wouldn't a Torsen be better for your use?

A 10 bolts w/ new Torsen + a spare assy might be better than one nine bolt w/ the German diff.

IIRC, for 28 spline 10 bolts, they make a Torsen (used in 99-02 F-bodies) and a Torsen + (T2R?) which has a friction preload based assembly built into it.

 

i had a ten bolt on there with a good posi........but i just HAD to have disc brakes...and it had drums.........so i sold the thing and bought the 9 bolt back before i knew anything about them.....it looked clean and it had disc brakes......now i know more! i guy i know has a moser ( 12 bolt??) it looks HUGE under there.......but i'm sure it can take allot of abuse..........

 

Are you interested in a 12 bolt?

 

well i haven't really looked into them yet......what are they worth? do you sell used ones or new?

 

For some reason I can't send a PM.

Nevermind, I got it.

 

I would use the c-clip eliminators thats the nice thing about the 9bolt its allowed the way it came alot of c-clip rears u cant use.. still wondering if the guy did the job right