Rear axle identification

[gtxno1]

Hi everyone how do you know what the car came with for the rear axle decoded the vin and the fender tag did not say anything 70 cuda

 

[Chryco Psycho]

Build sheet will have the ratio .
Most came with the 8.75 diff unless it was a slant 6 or a low option 318 which could have a 7.25 ".

 

[gtxno1]

I have searched under all seats including the rear yes it is 8 3/4 I was trying to determine if the ratio actually did come with the car just got the car will be restoring soon came through as a 340 hp car 3 spd manual on the floor trans is long gone

 

[EV2RTSE]

I sold an automatic transmission to a guy in Freehold for a '67 GTX years ago, was that you by chance?

In answer to your question, 3.23. Anything else would be coded on the fender tag as an axle package. No axle code on the tag = 3.23

 

[gtxno1]

I did buy a hp trans I drove to Maryland I think if it's you I picked it up at your job you worked at a dealer

 

[gtxno1]

the cuda has 391 sure grip do not know if it came with it no build sheet this thing has been sitting partially apart for 22 years missing a couple things trying to round up and start the resto

 

[EV2RTSE]

Oh must have been someone else then, I was living in Marlboro at the time.

For your car to have come with the 3.91 it would need

Code A31, High-Performance Axle Pkg (Not avail. w/ A/C)
(For 340 & 383-4 w/4 spd or auto)

3.91 ratio
Sure-Grip
7-blade Torque Drive Fan
Extra H/D Susp.
26" Rad. w/Shroud

 

[gtxno1]

Yes lol that was me I bought 2 of them how are you I still have the car

 

[gtxno1]

This cuda I will be cloning into an aar

 

[EV2RTSE]

Hey cool, small world sounds like a great project. Best of luck with it!

 

[Rons340]

You probably wouldn't be lucky enough that the ID tag was still attached to the third member. Thought I would at least bring it up. It's hard to believe but when I dissembled my '72 Challenger for resto. it was still there. 3:23 ratio, by the numbers a 340/automatic car.