# 1970 Pontiac GTO 455 HO 12 bolt posi rear diff ???



## bs_chevelle (Apr 14, 2021)

Several years ago I purchased a 12 bolt rear-end out of a 1970 GTO and ran in my 1972 Chevelle while I built a new 12 bolt for racing, once I put the newly built 12 bolt in the Chevelle I hung onto the GTO 12 bolt rear-end as a backup that I never needed. For sanity sake I would just like to confirm that what I have is actually a true 1970 Pontiac GTO 455 HO 12 bolt posi rear-end.

The axle tube is stamped with "XT K029 E"

The diff housing is cast with GM2 DN M(Boxed) 3969278

Looking forward to any comments.....


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## 67goat (Oct 27, 2006)

Date code makes it plausible. I don't claim to be a 12 bolt expert but my own interpretation of the codes seemingly mean it was cast in the Canadian Pontiac plant which would be unusual for a 10 bolt car, maybe not so for the 12 bolt. If it was originally a limited slip, I believe the E would stand for an Eaton unit - opening up could verify. I'd recommend checking codes with a reliable source. If in fact out of a GTO, would be relatively rare for 1970 due low production numbers for the 455.


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## O52 (Jan 27, 2019)

67 Goat is on the money. The code is found in the 1970 Service Manual and is for a 70 Grand Prix or GTO. 3:07 ratio, M40 automatic, 455 engine (no HO 455s in 70). Canadian built with an Eaton Posi. Listed as a type 'C' Safe-T-Track.


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