'69 RA 4 rear in a '71 GTO

[Alaskahovercraft]

What is this housing? I have a '71 GTO; was probably factory 3.23 open: 400, th400, air. What's in the car now is a housing with these casting #'s: 9795084, CFD 1 and 233. The axle stamp is a solitary 'H'. Can't find any indication of a 'W' or a 'Z' in front of it. Research indicates that the 1969 GTO RA 4 used this casting #, but nothing I can find indicates that this casting # is exclusive to a '69 RA 4 car; could this casting been used in other years or models...or even makes? Pontiac only made 700 RA 4's in '69. Who knows how it got in the car. WH code is open, ZH is posi; both ratio's are 3:55 for 1968 through 1972. I've examined the brake drums, and they are OLD. No stamping on the drums but the casting codes are KH and 74438 or 74439. I will attempt to add photo's. The gears in the car now are aftermarker Richmond 3.90's. I do not know the axle spline count or if they are 'C' clips or bolts. Any thoughts on this thing are appreciated, especially HOW to uncover the missing 'W' or 'Z' IF it was even stamped in the first place. Thanks, Steve.

[monzaz]

Hey Steve, Will see what we can come up with-
Start with that casting- 9795084 was used in 1969 with 3.55 3.90 4.33 rears and a 4 pinion super duty posi IF it was posi ONLY 3.55 was in a OPEN NON POSI version if it was 3.90 or 4.33 it was ONLY POSI optioned.

NOW since you have a H I am sure you have a 3.55 as ALL years from 65-72 it never changed - This code stayed consistent WH OPEN XH POSI IN 1969

That rear casting 9795084 seems to only be in the 1969 year GTO

The rear will be 28 spline and have BOLT in axles- Axle bearings could be sealed or oiled from internal gear fluid. It was a switch year.

Uncovering the stamp- Well considering the housing is pitted enough to hide the stamping i would say you will only get minimal from it anyway as most guys want super clean for all out restos. Does not mean someone will not pay a good chunk of money for it... Just might be costly just to make the stamp surface with acid etc.

Jim

[Alaskahovercraft]

Thanks Jim...I see that I mis-identified the posi code. I know this is a Nodular case becasue of the 'N' on the front of the center section, and I do believe it was a factory posi only because the original limited slip fluid tag was still on the housing; no matter. Someone blew it up way back when, ( gouge in the inside rear cover ) and then installed open Richmond 3.90's. I still don't know if this casting is exclusive to Ram Air cars or generic to ALL 1969 GTO's. I'll keep digging, and will certainly convert this to a 3.08 posi. Talk to you soon, and Thanks again. Steve.

[monzaz]

RAM AIR will definitely use the 'N' housing and in the 1969 your housing would be used. So if you advertised it as such you would NOT be lying. AS to the exact car it was in the code STILL would not tell you. You can have a Nod housing in a regular GTO also with any ratio. AS LONG as you check the box and paid the money. EVEN if it was not an available option...some one at the dealer ship could make it happen. MONEY, money, money....