What rear axle case would a 1968 super bee originally have?

[hqtrqd68]

Hello all. I was under my car today looking at the 8 3/4 in it. I noticed it had a 741 case. I would think it would have had a 742 case being it is a 383 4speed. I don't have a build sheet or trim tag unfortunately to reference. Any educated guesses from the guru's on what it should/would have been. Thanks! Peter

 

[Jerry Hall]

My 67 383 cars have a 742 case. I say 68 would be the same.

 

[33 IMP]

I agree, I would think a 742. But the assembly line ain't gonna stop if the right center section isn't available. They'll use what's handy.
Has it got a sure grip?
As for the 741, don't put slicks or drag radials on it, should be fine.

 

[pnora]

Here is a copy and paste,
1-3/8" small stem pinion... (a.k.a. '741')...

Carrier casting numbers: 1820657 (1957-1964), 2070741 (1964-1972).

This assembly was typically used in low weight/low horsepower

applications through low weight/medium horsepower and high weight/low

horsepower applications.

Pinion depth and bearing preload is set with shims. Differential

bearing setting (ie. backlash ) is set with threaded adjusters.



1-3/4" large stem pinion... (a.k.a. '742')...

Carrier casting numbers: 1634985 (1957-1964), 2070742 (~1961-1969).

This assembly was replaced by a phase-in of the 1-7/8" pinion starting

in the 1969 model year. 1970 RW (Plymouth and Dodge mid-size) were

the last models to use the 1-3/4" which appeared in a 2881489 case.

This assembly was typically used in high weight/medium horsepower

applications through high weight/high horsepower applications.

Pinion depth and bearing preload is set with shims. Differential

bearing setting (ie. backlash ) is set with threaded adjusters.



1-7/8" tapered stem pinion... (aka. '489')...

Carrier casting numbers: 2881488, 2881489 (1969-1974).

This assembly was introduced in 1969 and was phased-in to replace the

1-3/4" unit through 1970. Note: the 1-3/4" pinion also appeared in

some '489' carriers during this period. By 1973, the '489' was the only

unit available in passenger car applications.

This assembly was typically used in high weight/medium horsepower

applications through high weight/high horsepower applications.

Pinion depth is set with shims, preload is set with a crush sleeve.

Differential bearing setting (i.e. backlash ) is set with threaded adjusters.

 

[GTX JOHN]

I have never seen myself a 489 case that Did Not have a 1 7/8 tapered pinion!