10" rear brake shoes- circle vs rectangle hole for parking brake

[benguin]

Hi all- while attempting to do a major detailing of my 10x2.5 rear brakes, I ran into a problem where I received shoes with a rectangular cutout when their catalog shows a circular hole for the parking brake lever. In researching, I'm finding both versions show up for e-bodies and the application apps for the vendors don't distinguish anything different by year. It's clear they aren't interchangeable. Is this a year to year difference that the vendors don't account for? My favorite Mopar dealer (and sponsor of some sites) shows the rectangle version, but my Nov 1969 build clearly needs the round version.

Anyone know the history between these two versions which fit a LOT of Mopars?

 

[413]

Yes A 70 should have the round hole. they changed from the round hole to the other hole, not sure when they changed over. I had a 1978 mopar with the other style. It’s quick to install the lever in the hole, no clips. The 10” and 11” are this way.

 

[Katfish]

They are interchangeable, there is a washer/clip that secures the lever.

 

[benguin]

They are interchangeable, there is a washer/clip that secures the lever.

Not sure about the interchangeable part (at least for my '70), as the parking brake lever is a bit too large to fully seat in the trapezoid. I did think about drilling it out, but after considering the potential failure mode, I opened a ticket with the manufacturer's technical hotline. To their credit, they researched pretty throughly asking for several pictures of the old/new shoes, the stamped info on the new shoes and the UPC code from the box. Their engineers and quality team confirmed the issue and found there were some mispacked shoes and are sending a new set to me (Raybestos).

Here's a picture showing the lever fit on the old, and inability to get the shaft seated in the new- not even close to being able to get the washer and horseshoe slip on it. Plus the currently pended installation and clean up of 45 years of brake dust.

Lesson learned for me to check for exact match right away before disassembly.