Backing plate question.

[Undatker69]

Are rear backing plates the same for a 8 3/4 and 9 1/4 diff the same on C bodies?

 

[Polara_500]

I *think* as long as they're for the same size brakes they'll interchange. I don't think you can swap 2.5" and 3" shoe backing plates.
What I do know is I have changed 8.75 and 9.25 rear ends in my truck - and just took the brakes loose from the axle housing and hung them in the air and bolted 'em back on the other housing when it was in place. Didn't even have to bleed.

 

[Davea Lux]

Backing plates should work. If you were changing shoe sizes, that will take a different backing plate as the wider shoes require a backing plate with a different off set to accommodate the wider shoe. The '70 parts book shows three different backing plates for the three different shoe sizes and they appear the same for both axles. Your best bet is to check the parts book for the year of axles you are installing to verify the part number for that particular unit. Standard shoe size for '70 2" rear, backing plate #2880626 (usually with 6 cyl), For 2 1/2" shoes Backing plate #2880646-7, For 3" shoes Backing plate #2880648-9. These backing plates were used for a wide variety of years.

Dave

 

[Big_John]

I think that they will work, but the best way is to verify the part numbers and the easiest way is to look in the parts book.

Download a parts manual here: MyMopar - Mopar Forums & Information - MyMopar Tools/Reference

 

[Undatker69]

Thanks guys.

 

['69FuryIIIConvertible]

Yes, they are the same, 8. 25/8.75/9.25 and Dana 60 all use the same pattern to attach them, all backing plates have 5 holes punched, the 8.25 uses 4 of the 5, 8.75 and Dana use 5 of the holes and I can't remember without looking at the one beside my shop how many of the 5 holes the 9.25 uses.

Nick

 

[Undatker69]

Thanks Nick. This is my first Rodeo as far as Mopar goes. Been a GM guy up until now. All the knowledge injected is greatly appreciated.

 

['69FuryIIIConvertible]

Thanks Nick. This is my first Rodeo as far as Mopar goes. Been a GM guy up until now. All the knowledge injected is greatly appreciated.

Glad to help.

Nick