Brake Booster Life?

[Simon S]

sorry to put this forth in discussion.. my light searching efforts didn’t pull many results..

Nutshell: expectant life/mileage/maintenance span of a factory/original brake booster?

Car in question is: ’91 318is w/ something like 140K miles on it. EXTREMELY! well-maintained.

I’ve replaced cylinder seals, most all hard-lines, fluids, caliper rebuild kits, pads, rotors, bla, bla, bla.. all out of general “refresh” endeavors.

What I have NOT done is remove/replace the big/black/circular thing mounted to my firewall.

Does it have a life-span?
What life-span does it have?
I don’t want to worry about the brake booster being a weak link in my car’s system – is a functioning booster worth replacing?
Is a booster considered a “wear-item”?
Are my booster-concerns easily addressed with some sort of re-build kit?

These are my questions..

[Earendil]

X2. I'm interested in all those as well.

[jlevie]

A brake booster can last a really long time. The usual cause for early failure will be a bad master cylinder that leaks brake fluid into the booster. That fluid will attack the diaphragm in the booster and destroy it pretty quickly.

The brake booster is not rebuildable in the field.

[Simon S]

10-4
Input appreciated.