1965 GTO rearend code
 

I need a rear for my GTO but can not find what the casting code should be. Does anyone have any info or a sight I can go to to find the code ? I know the axle code is YH and the date is J,K or 1st week of L if anyone has a lead on one. Thanks

Casting #9779822 date code is next to it is. letter day year k 12 4 ect.

64 car is different......66 up is wider........65 one year only!

1965 GTO rearend
 

When I google that code it comes up as an Olds rear. The guy who has the rear says it has only 1 rib on each side of the carrier which shows to be a Buick rear.:confused:

1965 GTO rearend
 

Could that attachment showing the 3 style rears be for years other than 1965 ?

What I wrote my be the only thing I know about a GTO. LOL
Not sure if Olds shared it or not. They call them BOP rears?

There were different foundry's casting cases and there were up dates. You may see a larger 1 or 2 or 3 ect. on case. But this is not important. If you are looking for a date code to match your Dec car.

If its wrong some one will chime in

I have an available '65 Pontiac rear, but a May '65 date code. I believe it is stamped for a 2.78 axle ratio IIRC.

Olds for sure and maybe Buick also apparently did share the same center casting.

9779822 is a Pontiac engineering issued part no. It is for the casting only and does not identify the Axle Tubes & Diff Housing assembly.

What I do not know is whether Olds (or Buick) used different axle tubes pressed into the center casting. So I cannot say if a '65 Olds Cutlass rear Housing is completely identical to the Pontiac. Possibly same Housing Assembly but different ring & pinion gears were offered, I just don't know anything about Olds to be sure.

The stamped codes will be different for sure but that is a trifling matter.

If all the dimensions are correct, then I would say it will work for you.

If you need dimensions to compare it to my Pontiac Housing just ask.

1965 GTO rearend
 

Is that a picture of your rear from your 65 or a picture you found online ?

Picture is from file.

I have 64 and 65 housing and a 70. all are different in some way. But all these will bolt in.

64-65 is 54.25" flange to flange.........66 up is wider 3/4"

The gears and case interchange. Case is different for different gear ratio's. Check with people that sell gears and cases for interchange.

More help. Note date. This casting # 54.25" wide and you found the correct housing. Gears and carrier you may have to change.

1965 GTO rearend
 

Is the rear for sale or another one that you have ?

Ask John V first He was first to post one. But the 64 I will sell. Have housing only.

1965 GTO rearend
 

Johns is dated for May, I will need a oct,nov or early dec of 64. What is the date and axle code on your 64 ?

My 64 rear is cast in 63. Yes you need the housing that I posted pic of. Thats for my 12c 65 car. Sorry.

Remember if its about the correct Date the 64 rears won't help you, diff. casting # and they look way different. You need 9779882 casting. The year is cast in the housing remember.

Any chance at all to purchase your 65 housing ? Maybe put an inflated price on it.

What is the gear ratio code ?

No .......can't help With that. Will PM u if find something u can use.

Is the casting code for your 64 housing 9772969? What is the date code, please? Thanks, JBA

65 rearend
 

This rear is for my 65 GTO. The casting code is 9779822 and the date I need is K or early L of 1964 with a gear ratio code of YH.

PICTURES Very few pits in tubes.