Brake drum backing plates, looking for.

[jntrndrm]

I'm looking for the rear backing plates for the 2-3/4" drum brakes , I haven't seen them any where. this is for an 80's 5 lug rear end.  Thanks for any help.  Don

[elijahcollins688]

These might work for you but I’m not sure. https://www.summitracing.com/parts/ado-15650129

[elijahcollins688]

I also am having troubles finding backing plates for my 12 bolt truck and can only find them for a 12 bolt passenger.

[Fast68Chevy]

75 76 77 78 79 were the years most common for the BIG 10 and F44 big brakes 2 3/4"  were billions of them out there.  these are the plates you bolt onto the 69 and older housings to be able to convert them to 5 lug and use 5 lug shafts 71-up and make axle the same width as the later years ones.   this makes up the 1.5" width difference  3/4" plus 3/4"

[Ronno6]

The backing plates for the 11.15" x 2 3/4" (JB5) have 3 different part #'s for the years '74 to '87:

74 to 75 .....331447, 331448
76 to 82 .....357853, 357854
83 t0 91 .....14055278, 14055279

I believe they will all bolt up to 10 and 12 bolt housings, but am not sure what other differences exist.
They use the same shoes and drums.
I do not see the JB5 option for '73.

Now the disclaimer: This information is the result of my research from GM parts manuals, and is in no way guaranteed to be
valid beyond the information contained in those publications.
I urge you do do your own research before investing in any of the above parts for your particular application.
(I feel much better now....)

[Ronno6]

Any y'all still searching for JB5 backing plates, I BELIEVE this seller has some:

https://www.ebay.com/itm/GM-10-bolt-differential-backing-plate-and-break-parts-drivers-side1/112356456902?hash=item1a28f779c6:g:rH4AAOSw3utY4RuD

https://www.ebay.com/itm/GM-10-bolt-differential-backing-plate-and-break-parts-drivers-side2/112356454654?hash=item1a28f770fe:g:q0EAAOSwU8hY4Rrx

https://www.ebay.com/itm/GM-10-bolt-differential-backing-plate-and-break-parts-passenger-side2/382027386941?hash=item58f29b503d:g:D8sAAOSwCU1Y4Rh9

I THINK they are 2 3/4" wide shoes, but you should contact him to verify before buying.