Front brake problem

My front brakes suck,
Others driving my truck noticed,
All I noticed is every year at inspection the mechanic replaced the front driver side caliper 4-6 years in a row,
This year I lost my brakes totally, and I noticed my truck starting to smoke out the exhaust weirdly,
thought this was it.
brought it to a different mechanic, he replaced the master cylinder, but he knew that wasn't it,
So he replaced the booster,
The booster was almost full of brake fluid,
Some how the emissions vacuum was sucking fluid into the booster and after it filled up to a certain point it some how flowed into the engine and caused the smoke.
It seems to be going back to the way it was.
Any body else have this?
Suggestions?

 

There is a check valve on the booster. Is it possible yours is bad? It’s an expensive part, but looks basically like a 1” round bung with a vacuum hose attached at the 9 o clock position at the booster when looking from the headlight.

No idea what’s causing it otherwise. Many people have complained about the same, fluid in booster. I dunno why it happens.

have you noticed the pedal is hard when you sit in the truck, before you turn the key?

 

I park it facing up hill lately so the bed drains out,
Would you think that makes a difference?

 

IMO, it shouldn't.

 

I was just trying to figure out if what besides the emissions vacuum was causing the brake fluid to get into the booster,
Was thinking the vacuum caused a siphoning type senerio and then the gravity helped it succeed.
I can't believe it actually brought brake fluid to the cylinders.
Wicked weird.
Thanks for your input dude

 

Brake master cylinder leaking into the booster, again?

 

When the MC goes bad and leaks at the pushrod, the fluid can get into the brake booster. If enough accumulates engine vacuum will suck it into the intake which causes a smoke show.

 

Huh???
Thanks