Seeking edgucation Y did GM install Bendix & Moraine into these trucks?
 

I think the kits are limited to a booster option, combo prop valve, master cylinder, and some or all the brackets. Perhaps some brake lines too, not sure.

What do you like best OT, metal finish or black? Personally I like the looks of the Bendix a pinch more, old school black.

Anyway, why did GM install both? Perhaps Moraine is heavier duty, hmm.

Re: Seeking edgucation Y did GM install Bendix & Moraine into these trucks?
 

Always preferred the Delco Moraine design '71-'72. Maybe Delco couldn't keep up with the demand, so they went with Bendix for some of the trucks. Doesn't seem to be a rhyme or reason to which trucks were equipped with.

Re: Seeking edgucation Y did GM install Bendix & Moraine into these trucks?
 

Here is an old write-up from Livrat from outintheshop site about the different boosters.

https://outintheshop.com/faq/Brakes/brakeinfo.html

I prefer the Delco Moraine booster in gold zinc dichromate.

https://www.brakeboosters.com/brake-boosters-history