It looks like the Raybestos and the Dr Diff are the same except for price. Am I able to get just the 4 to 2 bolt adaptor and longer rod separately? The Raybestos is a lot cheaper and looks readily available at any parts store.
I’m not 100% sure that the Raybestos unit is machined to accept a manual pushrod. You didn’t mention if you were using manual or power disc brakes.
The manual master has a recess groove in the bore where the pushrod goes to accept the pushrod retainer (
Mopar Manual Brake Push-Rod Retainer, Bushing, Clip Rubber Grommet ) I know the doctor diff units do have that and am not sure if masters made for the early 80’s and mid nineties cars have that accommodation.
The Raybestos unit from RA doesn’t include the adapter and grommet……
Doctor diff stuff is brand new and made to his spec in Taiwan, and the raybestos is made in China. I have also ordered other 2 bolt masters in the past that I thought would work, but more than half of them showed up and were cast iron even though they say made of aluminum, from the other half 80% of those showed up with the wrong reservoir, and the remaining 20% of those came with the wrong bore diameter.
By the time you order the rock auto one, an adapter, and a grommet separately from somewhere else with two to three separate shipping expenses you’ll probably be behind $15 - 20 bucks vs just ordering it all from one guy - Doctor Diff. Doctor Diff also offered a 15/16 bore diameter which is good as it increases the clamping force of the brakes, a little less pedal feel but nice to have. If you choose the 15/16 bore it is an up charge of 30 bucks, which will bring your overall net cost to close to the same as the hodge lodge solution.
Lastly, if you’re changing from manual drum to disc you will need a proportioning valve, which Doctor Diff Also sells (one stop shopping). It will be a modern newer A body style which will bolt right up where your original does and the lines will screw right in. I’m adding this info as I can’t be sure if you have the proper early disc pro valve or just a distribution block without seeing pictures of what you’ve got going on.
I also choose to order and support a small guy who actually also owns and is a mopar enthusiast which supports our community. If you have a problem with rock auto, good luck getting ahold of them on the phone or email reply to discuss tech support and what your options are. Cass from Doctor Diff will help you out.
To me the choice is clear
