# 69 GTO Diff code



## Jimsgoat (Sep 1, 2018)

Guys, I'm a novice and trying to find out what diff I have in my GTO. It is a ten bolt.
I can only find numbers on the rear of the diff. I can't see any numbers on the axle tubes or tags on the brake backing plates.
The digits on the diff are...
K188
9795082
(I think) photo attached.
Thanks
Jim


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## histoy (May 22, 2019)

Those are the date code when produced and the casting number of the diff housing. They have nothing to do with the gear ratio of the diff.


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## PontiacJim (Dec 29, 2012)

The axle tube is stamped with a 2-letter code which can ID the gear ratio. It will be a couple inches out from the center section stamped somewhere on the axle tube. You may have to really clean/ wire brush, or greenie pad the area to find it. Took me a while to uncover mine and I didn't think it had one as well.


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## integrity6987 (May 10, 2017)

If you can't find the codes - you can always figure it out by putting it on jack stands with the car in neutral and count the # of revs the driveshaft makes for one rev of the tire.


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