2001 Tundra TRD AC - Brake Booster Issues

I have a 2001 Tundra TRD Access Cab 4.L. Frame replaced by Toyota in October 22 and they replaced the brake lines. Also, brakes new all around. So I was hearing a hissing sound and took the truck to my mechanic.. they told me it was the brake booster. I ordered one from rock auto (quality built brand) and took it for them to repair. 10 minutes after picking up the truck the pedal got really stiff and was difficult to push down … I ended up towing it back to the shop. The said that I bought a faulty booster. I told them to order theirs and complete the repair. They ordered 3 diff boosters from different manufacturers and had the same issue. They ended up reinstalling the original booster and the truck ran fine… hissing sound is back. I am currently look for a used one on eBay since Toyota discontinued it… anyone have similar issues?

https://www.rockauto.com/en/catalog...65,brake+&+wheel+hub,power+brake+booster,1884

 

This is only the dozenth thread I've seen in this forum over the last four years or so with "I got an aftermarket booster, and suddenly my brakes suck".

Wish I could tell you why it's the case. I think I'd live with the hissing, is it possible the hissing is the check valve or its grommet?

 

I’m not sure what’s causing the leak tbh. I just ordered a used OEM master/booster assembly from yota auto parts on eBay. Hopefully that solves the issue.

 

The check valve is this thing. It's held in with a rubber grommet that's replaceable and rubber hardens with age. It's attached to the intake manifold with a vacuum hose. The check valve is one-way.

Not saying that's it, but it's something I'd be checking. There are other things internally that can hiss (booster failure) but I'd expect you to notice a difference in performance. If the boosters you installed had a new grommet, and they weren't hissing, and the new booster is still hissing ... could be worth checking.

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Okay I’ll check it. Thank you!