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Well, got to tinkering with the truck today and noticed a black patch of stuff on the outside of the vacuum pump. Investigated it more and I believe I have some bad carbon buildup on it. Now I would like to know if my pump is cleanable or do I start looking for a new one? When driving my truck and you go to brake, its like trying to stop a freight train and oddly enough my father's 96' F250 PSD stops on a dime. Would the vacuum pump be the reason?
Is your exhaust manifold leaking above the vacuum pump?
You need to check the vacuum it is making, that could easily be your problem stopping.
The 96 model may have hydraboost that runs off the power steering pump for the brake assist.
Hydraboost is a real step up in braking power.
A vacuum gauge on the line from the vacuum pump to the vacuum tree located on the fire wall is a good place to start. Then you can plug that line back in and add all the other lines one at a time with the ports blocked off till you put the line back on.
If the reading suddenly drops when you plug a line in, you have a problem in that vacuum circuit.
If it is not a manifold leak, the black is engine oil and dust instead of carbon.