1990 Ford F350 diesel here. I just replaced the vacuum brake booster on the truck as the old one was leaking, and I think having the additional “boost” has helped to identify a different problem.
Most of the time when I press the brakes I have to get on them pretty well to bring the truck to a stop. nothing dangerous or too out of the ordinary…but I assumed this was normal as every truck/car has a different feel to the brakes. HOWEVER
Sometimes, for no apparent reason I will suddenly get a ton more braking power with much less pedal push (I think in my front wheels) - I will depress the brake pedal as normal…and the brakes will start working as I expect, and then all of the sudden, I get a TON of brake power all at once…if I happen to be pushing hard enough the front wheels will completely lock up. Then after the first occurrence they will be touchier than usual for a while and eventually go back to being normal…
I suspect this is a stuck caliper - or possibly something to do with the master cylinder? Thoughts?
Thanks in advance!