*8 3/4 Questions

[72 fishbone]

So I have a 1972 Barracuda with an 8 3/4 rear end with 489 casting running 3.23 gears just took it out for a drive about 40 miles and noticed that upon return to my home that the rear end is very hot so I shot it with a temperature gun and it's showing 168 degrees on the outside case is this normal or do I need to investigate further? any bit of information would be greatly appreciated.
Thank you
V/R

 

[72 fishbone]

Problem solved found out that my bearings are shot surprised that it didn't explode on me while driving down the road......

 

[moparleo]

Try to find a 742 chunk to replace the 489. 742 actually stronger and has the good, rebuildable type sure-grip. The Auburn type like the 489 takes are not.

 

[70Hardtop]

Try to find a 742 chunk to replace the 489. 742 actually stronger and has the good, rebuildable type sure-grip. The Auburn type like the 489 takes are not.

Not sure how you can say the 742 is stronger. The 489 is way stronger as it has a much thicker input shaft. With the crush tube eliminator kit, these are the 8.75 of choice. The 741 is the smallest, next is the 742. Also, not all 489 cases were Auburn /Borg Warner style SureGrip, although most were. There were many with the Dana type clutch PowerLock as well.

 

[moparleo]

Mopar Rear Ends / Differentials / Etc
http://www.planethoustonamx.com/main/chrysler_8_34_rearends.htm

Here are few good reads on Mopar 8 3/4" differentials and have a lot of good info.

Put them in your save folders for future use.

 

[Cudafever]

this is how i will argue with the "which is better 742 or 489"
Go out on the net and find out how many gear ratios you can get with a 741 housing these days..... here's a hint there is only 2 gear ratios available.
then see how wide of gear ratios or available "TO DAY" for the 742/489
I don't like the crush sleeve but that can be fixed..........489 wins in my book.
If you can't get the gear ratio you want..........Who cares if it is stronger.... or not!

 

[Daves69]

There is a "one-time" fix for the 489 cone SG. Rusty on FABO has a tutorial in the "How To" section...............
Articles | For A Bodies Only Mopar Forum

Dr.Diff has the crush sleeve eliminator for 30 bucks or so.

 

[Cudafever]

Yup got the crush sleeve eliminator and have a clutch style sure grip.
How ever, That is a GREAT ARTICLE, if you have a dead cone style.....sure beast buying a new one because they're not rebuildable...... Wink wink.