It has to be the Brake Booster...Right?

Just to close the loop on my questions above:

1) Yes the pictured brake booster was OEM, which I figured out after looking at more OEM boosters from junker trucks and confirmed by the expert described below.

2) Steve is the best. Don’t pass Go, don’t collect $200–if you’re in Southern California just take your brake component to Steve and watch the marvel that is Bush Power Brake Services unfold before your eager eyes. Steve has clearly been working on brake components for longer than most of us have been alive. Guy reminded me of my grandfather who was a Caterpillar mechanic for most of his life—old school seasoned hand at doing things right the first time and exactly what I was looking for. He rebuilt the booster with new seals and diaphragms and then took the time to explain to me how it works and why it had gone bad. His shop exudes organization and he has this lean craftsman frame and surgeons hands—not in a hurry and focused singularly on solving my problem. The guy has just rows and rows and cabinets full of carefully labeled parts. There was about a dozen sets of boosters and cylinders lined up for pickup when I showed up this afternoon, so he’s clearly in demand. I could be wrong but I don’t know of anyone like him in the Bay Area (I asked if he knew if there was a “Steve of the North” and he said he did not). Many thanks to Glamisman for this enchanting find. Also, National City (where Steve’s shop is) is a fascinating town that’s basically the last thing in the US before San Ysidrio—easy to jaunt down to TJ for a taco while you wait on brake work. @stevebear1949 although I think the social media profile is being ghost written a little or a lot since Steve is way more salt of the earth than the captions would suggest.

Rebuilt booster, couple of hours and $275 plus tax, which is immensely reasonable seeing as the OEM ones are $800+ if/when available.

 

I think having it rebuilt by a pro is the best bet if you can. I bought one from a chain store about 5 years back (OEM already discontinued at that time). I hate to buy parts from the chain stores but it seemed like that was the only game in town. Also it was not painted.

The real problem is the adjustment on the part that pushes the master cylinder. With most manufacturers they spec a spacing between the brake booster push rod and master cylinder and its not trivial to get this right. With Toyota they just say "use our special tool XXX".

So my brake pedal is bit low and really sucks, within spec but barely. I actually tried to adjust the booster push rod but I think they put red locktite on it so its not moving. Anyhow as you can imagine trying to adjust by trial and error would involve at least several master cylinder removals/bleeds.