318 Challenger-what decided the rearend?

[bb71challenger]

My car had a 8-3/4 rear in it from the factory, I had a /6 parts car with an open 8-3/4 and low miles so I am assuming it was factory. What determined which rearend the low horse cars got? I always wondered why those cars did not come with an 8-1/4 

[resq302]

Yeah, I've wondered that too since our chally has a  8 3/4 in it too.

[71chally416]

Had a '72 slant-6 Cuda with an 8 3/4.

[426HEMI]

Let me try to explain how it was at the dealer I was at.

The dealer ordered certain things each time on the cars and it did not matter if it was a 6 or an 8.  He was looking at warranty costs on what it would cost to fix it.

Or that is what he customer special ordered when the car was originally bought.

Or that is the rear end they had at the time on the assembly line.  Or the dealer knew someone that worked the assembly line and had it changed. 

I have seen all of this happen.

I hope that helps

Gordon

[HemiOrange70]

In '70, 318 Challengers came with the 7 1/4. You could upgrade to a 8 3/4. 71 and later the 8 3/4 was the base rear. THe dealer or customer ordered whatever they wanted for gears

[Alaskan_TA]

The differentials came as an assembly, including the brakes. See this page for what combintations were available in 1970;

http://www.hamtramck-historical.com/images/TSBs/1970/D70-3-2%20page4.jpg

['Cuda Hunter]

My /6 1971 barracuda has a 7 1/4 rear end.

[bb71challenger]

So it was 7-1/4? Man that seems little. I always thought it was 8-1/4

['Cuda Hunter]

I always thought it was an 8 1/4 until I purchased a car with the original 7 1/4 still intact.