Mopar Third Member (741 742 489) Interchangeable ???

[DaWeezzz!!!]

Greetings,

Confusion Here!!! LOL!!!

Are Mopar Third Members, Pumpkins, or (741 742 489) Interchangeable with all A bodies, B bodies, & C bodies that have a rear 8 3/4 Axle???

I have a 1974 Duster that I'll be switching out to a 8 3/4 rear axle and wanted to see if the Third Members were Interchangeable. Or, are there different Third Members / Pumpkins sizes for each series of cars? So, will any (741 742 489) work on any Mopar Car with a rear 8 3/4 Axle?

Please let me know. I don't know jack about this stuff and don't wanna buy the wrong one. Thanks...
Alec

 

[Demonracer]

Any of the third members will work in an 8 3/4 housing. Just make sure the spline count on the axles are the same as the spline count in the third member.

 

[Demonic]

^ What Demonracer said. There are some spline and thrust block width differences, mostly prior to '65 iirc.

 

[Darter6]

^^^^ Some of the early sure-grips had 2-piece spider gears where the axle slides into.That may cause a problem do to axle length and not engaging completely into the splines.Later and replacement parts are one piece.Just something to look out for.
Look up Dr. Diff for 8 3/4'' info as he is the go to guy.

 

[DaWeezzz!!!]

Any of the third members will work in an 8 3/4 housing. Just make sure the spline count on the axles are the same as the spline count in the third member.

Thanks for the info....

Alec