11" backing plate on 8.5"?

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Vikingdude

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Like everyone here, I'm totally underwhelmed by my brakes. They are working correctly, I have a nice firm pedal, but the rear is just so darned weak. I looked but couldn't find an answer, will the 11" drum backing plate bolt up to the flange on a 10 bolt 8.5" rear end? I would love to swap the rear end, but I'm a LONG ways from a junkyard
It looks like you can piece together a complete setup from rock auto, but I can't find measurements on the bolt patterns.
 

Schurkey

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I learned just a week or three ago that the flanges (bolt circle) is different between the 8.5 and the 9.5 axles, so unless you can find the big 11.x backing plates to fit an 8.5 axle (unlikely) you're kinda screwed. That, or you "weld and pray" to either add metal to the existing flanges, and re-drill, or you just put new flanges on the 8.5" axle.

From https://www.gmt400.com/threads/10-b...le-shafts-and-big-wheel-bearings.60788/page-3
The 11" rear drums won't bolt on to an axle that came with the 10" drums. The bolt flange on the end of the axle tubes is different. You need the whole rear axle assembly to make that swap.
 
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