The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - Does this new master cylinder look correct?

**jocko** · 07-06-2023, 08:30 PM

Your new mc reservoir sizes are good to go for a disk/drum C10 setup, but your mc is for manual (non-power) brakes - this is the bore depth I think you are asking about in post #4(?). Pic in post #4 shows the deep bore in the mc piston. Power brakes require shallow depth hole to receive the standard intermediate pushrod (the little stub pushrod that protrudes from your booster). Recommend return your mc to swap for a power brake mc. There are other ways around this (custom intermediate pushrod) but getting the correct mc is easier in the long run, no guesswork involved. Sorry, probably not what you wanted to hear.

Out of curiosity - was this a power brake truck from the factory?
Also, can you confirm whether this is for a C10 or C20?

07-06-2023, 08:30 PM	#6
jocko Senior Member Join Date: Oct 2009 Location: Godley, TX Posts: 17,994	Re: Does this new master cylinder look correct? Your new mc reservoir sizes are good to go for a disk/drum C10 setup, but your mc is for manual (non-power) brakes - this is the bore depth I think you are asking about in post #4(?). Pic in post #4 shows the deep bore in the mc piston. Power brakes require shallow depth hole to receive the standard intermediate pushrod (the little stub pushrod that protrudes from your booster). Recommend return your mc to swap for a power brake mc. There are other ways around this (custom intermediate pushrod) but getting the correct mc is easier in the long run, no guesswork involved. Sorry, probably not what you wanted to hear. Out of curiosity - was this a power brake truck from the factory? Also, can you confirm whether this is for a C10 or C20?