Brake Booster Pushrod - Adjustable?

[Gibson]

I'm putting a new booster in my 78 c10 (JB5) and I saw a bunch of videos talking about adjusting the booster pushrod so there is no preload on the MC, but when I'm looking at the new booster (a TuffStuff 2232NB), I don't see any provision for that (like there are no threads or anything to adjust).

What I DID notice is that the pushrod has some o-rings on it that seem to give it some pneumatic cushion when you slide it in. Does the booster auto adjust or something using vacuum?

[tucsonjwt]

When I replaced my booster with an AC Delco one, it came with two different pushrods, a long and a short one. I used the pushrod that matched the one that was in my truck.

[Gibson]

I saw some people mention that too, but this booster only came with one rod.

The booster that was in the truck when I got it was the single diaphragm (JB3 style I think) but my truck is has a JB5 code so when I bought the new booster, I made sure to get the dual diaphragm. I figured the PO just got the wrong one from the parts store. The new MC I'm putting in is listed as a JB5 1.25 diameter bore. So I'm not sure they share the same style rod (although it looks identical to the MC I had before).

[Gibson]

Ok, I contacted Tuff Stuff (makers of the booster) and they said this booster does not have an adjustable pushrod. They do make two different push rods for it but the one that comes on it is for a "shallow hole" MC. I think the MC I have which is what I believe mine to be. I have the Wearever 10-1521 from Advance Auto.

They sent me a picture showing the style their booster was designed for (I'm attaching it) and mine looks like the "shallow hole" style. I guess there must only be two sizes and they are machined a certain way. Looks like they are significantly different in length.

I'm going to try measuring the rod on my old booster and see how much it sticks out and compare it to the Tuff Stuff.

I think our boosters were just designed in such a way as to not need adjustment?

[Dead Parrot]

When I got a replacement booster for my 75 from Autozone a year or so ago, it came with an adjustable rod. Turned out it didn't need adjusting. No specific SPID listing for the brakes but it did list the HD chassis. The old booster also had an adjustable rod.