Ive noticed something on my 95 that I have a question about. I realize the vacume pump need to turn a bunch to produce vacume, but it seems lately if I hit the brakes a couple three times in a row quick like, I loose my power brakes and the pedal is real hard. Say if I was inching my way down a decent 4x4 trail and was manupilating the brakes they`ed be gone real quick at idle speeds.
Any ideas?

 

I've never known these vacuum pumps to wear out, but I would think you have a vacuum leak. Tee in a vacuum gauge somewhere in the circuit, I think you should see around 20 inches at idle. The plastic line going to the cruise servo is a common leak spot, battery acid can eat it away. I've seen several leaking brake boosters on 1st. gen trucks, not on 95's but it's worth looking at. Run a stethoscope hose around the seam on the booster (at idle) and you will hear the hiss.

 

thanks, I`ll take a looksie. Last time I inquired about a pump on my 93 I was told dont even ask, $1200 or so? ouch. It seems to be fine during normal ops and driving. Hope its something simple.

 

If you're just idling around the vacuum pump can't keep up with booster demand, part of the reason for the switch to hydro assist in '97.
Some folks have added a vacuum reservoir tank to store more vacuum, DC has an overpriced tank setup just for this purpose. Cheap tanks are available for under $20 in the aftermarket or you can make your own out of a short piece of 3 or 4" pvc pipe with two caps with a port drilled and tapped in.

 

Never thought of the canister idea. I did find a bad line going to the cruise control. Im pretty picky about that stuff but I missed it last look. Thing was worn thru and twisted near in two. All better now.
Thanks again everyone.