I'm writing this cause I found a small thread in Transmissions about what is the correct tag for a '67 SS Posi.

I see in the resto-catalogs a thin metal tag listed for 66-72. I also see a red tag in year one, but it reads wrong listed for 68-72. And the parigon book shows a red tag for 66-72 which reads correct.

Looking at the filler plug on my 12 bolt posi with original gears and all, it doesn't have that flared filler plug to accept the red tag. I also have a friend with a '67 A/C SS with Posi and he doesn't have the flared plug either. Also the person that originally brought up the question in Transmissions says hes doesn't have the flared plug.

Which is the correct tag? Is it plant related? My rear says Buffalo/Eaton Posi, put in a Fremont,CA car.

Did they use both the tin and red tag? Just one? Which One?

I'm asking here, cause I want the CORRECT ORIGINAL look, not just a marker for the quicky lube guys.

Red tag.

My 67 SS had a metal tag hanging off of one of the rear cover bolts. I think it also had the red filler tag too.

I got to thinking about this, and you never know what people will do with stuff after 38 years. Its possible someone mixed up the plugs at a lube shop or something like that.

Guess I'll hunt the flared plug and get a red tag.

Incorrect:

http://www.chevelleinfo.com/etr/rearend/photos/positag.jpg

Correct:

http://www.chevelleinfo.com/etr/rearend/photos/posi_fluid_label.jpg

I doubt that someone would switch out their rear end filler plug with something else but you never know.

Dale, I still can't figureout the problem I ran into. Are you sure that there was not a different thread size change from 67 to 68 on? The later size plug with the tag would not fit my 67 "open" case.

Dave

To the best of my knowledge:

There are two sizes of plugs and red tags. The earlier housings use the 3/4 inch NPT (about 1 inch in diameter) and the later housings apparently use the smaller 1/2 inch NPT (about 3/4 diameter) plugs with smaller diameter tags. Corvettes including the mid year models apparently use the smaller diameter as the 68? and later Chevelles.

I had a 67 12 bolt housing (CF code) with the 3/4 NPT flared plug, and my current 66 12 bolt housing has a 3/4 inch NPT non-posi plug (it has a non-posi code).

The earlier Corvette (small diameter) and early Chevelle (large diameter) tags all indicate "positraction", and the later small diameter may have used "limited slip".

The red "positraction" tag I put on the 67 had a smaller diameter and really had to stretch it to get it on. I suspect it came off of a Corvette.

Bruce

Edit: I have a flared 1/2 NPT plug that I would gladly trade for a 3/4 NPT flared plug.

:clonk: Thank you Bruce,
I'm not real smart, but I know when a plug won't fit a hole.