Found that my casting number on the rear end is 3959038. It looks like it's never been out of the car. I show this rear end is for a 69'. Ratio is 3:31 non posi. This sucks.

That sucks brother! I actually thought for years that my rearend was a 69 (late 68 date casting), but when I finally looked up that other casting number I realized what looks like an 8 must be a 6...

http://i117.photobucket.com/albums/o67/TJ_Johnson/Other/Date_code.jpg

http://i117.photobucket.com/albums/o67/TJ_Johnson/Other/part_number.jpg

Also though, keep your chin up about that axle stamping deal. My "CW" should be 3.31 non-posi, but it was a posi.

http://i117.photobucket.com/albums/o67/TJ_Johnson/Other/AxleStamp.jpg

See a few threads down, I just picked up a CRW stamped '70 rearend that shouldn't be posi according to this website, but turns out also has a posi.

Your pic is the casting number that I need. I guess someone cut my 69' rear to fit a 67'.

:) jd - 67 , i've got those same casting no's on my 12 bolt , i was just about to look them up . i guess it's why the posi carrier , & 410 ' s came with the car when i bought it ! . i cracked the cover off , gears all look fine . have you ever seen ; ass , painted on the ring gear ? . i'm a rookie when it comes to diffy's . would you think i'll have to cut to fit a 66 beaumont ? , same frame as chevelle , thank's for any replies - tommy

Your pic is the casting number that I need. I guess someone cut my 69' rear to fit a 67'.

The width isn't that much different, it wouldn't necessarily have to have been cut to fit in your car. Are you sure it's been cut?

My two rearends measure 1 1/4" different from backing plate to backing plate, which means there is less than 3/4" lost on each side. Our '67 wheel wells are gracious enough to allow something like that. ...or a rim with slightly more backspacing would fix you up.

thank's for the info t . j , i dont think they have been cut , the axle tube lengths are equal - 18 & seven eights inches . i looked up the no's on chevellestuff 3959038 & directly after the no's , their is nf ? . mine does not have these letters . on the reverse side of the outer gear housing it has gm 2 d / n . also with a square outlined with a; m in it , on top of these no's . it also does'nt have cw or cf anywhere . on the axle it has ; L G . & only no's i can see is ; 911K , almost look like the rest have been grinded down for some reason , if their is more no's ? . any info back would be appreciated , thanks - tommy

jd67

The rear that you have will fit without having to be cut. Most people will never know, unless you try to get the car certified. Most normal car people will look at it as the factory rear.

Don't fret over having a non 67 rear in your car. If you do want a numbers matching rear, you can find them in different locations. A fellow TCer by the name of TLowe builds 12 bolt rears. If you really want a 67 rear, he might have one.

As you know, I have a 69 rear in my 67. I am just glad that I found out before getting parts. Measure it good before getting stuff, that will help.

Bill

:thumbsup: thank's for the info, bill . - tommy

I looked at the rear end again, it has not been cut. I did'nt know that the 69 and the 67 were so close in length. I was hoping it was a 67 rear, but 69 will work. Thanks for the info.