Hi there,
I am new here. I have an 84 D150 with a 2012 5.7 in it. I've owned it for 6 years and I did the engine swap about a year ago.
Its now time for me to take care of all safety related items (brakes, front end parts etc). After checking out what I'll need to replace, I found I'm in need of new rear drums, shoes, and backing plates. Drums and shoes are readily available, however the backing plates are not available ANYWHERE. I'm not even sure what size my rear brakes are to look for the proper backing plates and drums. I have attached a picture of my rear differential, can you guys tell me from the picture what diff I have and also what size drums/backing plates I should be looking for?
I've checked local salvage yards and all parts stores with no luck on the plates. Do you guys have any suggestions for me in my search for backing plates?

 

Looks like an 8 1/4 light duty truck? Van

 

That's what I thought as well. Originally thought maybe a 9.25 but the shape of the diff cover suggests a 8.25. Any idea where I can find backing plates for this rear end? Its a very common rear end but for some reason backing plates are impossible to come by.

 

Sounds rite. What Lynn said...

https://www.google.com/search?q=Mopar+Differential+ID&tbm=isch&tbo=u&sour ce=univ&sa=X&ved=0ahUKEwik5u2qra7YAhVB5yYKHZ3DC9gQ sAQIUA&biw=1848&bih=991#imgrc=jIDs0Amq7GWEnM:

 

Light duty 1/2T vans trucks , mid late 70's cars LOTS of possibilities What bolt pattern does it have ?

 

I think in the trucks it was called a 8 3/8 If my memory serves me correctly.