RoadDiesel

The reason I ask is, when I enter our cabin driveway, it has a steep hill & the engine is just idling. I used the brakes and it seems like I no longer have brakes when I get to the bottom of the hill, unless I rev up the engine a little. Then I have brakes...I also heard it is a good idea to replace the front brake hose's as over time, they are beginning to get fatigue ...1994..228,000 on the truck..thanks

Diesel Dave2

My truck has done that for years....I thought is was normal....

Is it normal..?

infidel

It's normal on the '94 - '96 trucks that have vacuum assisted brakes to run out of vacuum if the brakes are applied repeatedly while the engine is idling.
The pump just can't keep up at low rpm.
Best way to deal with it is just to be aware of it and lay off the brakes so much at idle.
Or you can turn the idle up or add a vacuum reserve tank.
I read of one guy who added an electric vacuum pump to help his keep up.

whiskers

Probably a crack in a line that you haven't spotted. There should be a resevoir tank already. Have you had any problems with cruise control not holding? Vacuum leaks will show there sometimes.

SIXSLUG

If your brake power returns immediately after increasing RPM, I would rule out swelling brake lines, however you may have a vac leak.

The usual spot is the vac line running at the top of the firewall under the hood. It has a tee and a cap that can deteriorate, at least mine did a while back.

the capped end on mine probably would go to the brake booster on your truck.

RoadDiesel

Thanks all..I will look into that this weekend..comments still welcome..oh..cruse control has always worked great & still does...

Gary 1994

I just experienced a lot of brake problems in a short time. Complete power brake failure first. Then the lights came on and stayed on until a restart of engine.
2 problems: I replaced the original vacuum line from the pump to the booster with parts from NAPA because if it were to collapse, then you will have no power assist. Old hose was really soft. Placing a vacuum guage on this line shows 10 inches at idle speed and 16 inches at higher rpm. This explains why the brake response is not great when first starting the engine a putting out of the driveway. Rev it up a little to get the vacuum booster going again.

2nd problem: The rear brakes were out of adjustment because I never hit the brake pedal while reversing for the most part. I pulled both rear drums and found the shoes glazed and took a file and used the flat end to scuff the shoes to remove the glaze. Then made sure the star wheel was completely freed up to move with the actuator. After repeated stabbing the brake pedal rolling backward down a slope the brakes are now better than many years back. 82,000 miles on original brakes. Manual transmission..I think the fact the brake pedal travel was too far the ABS light was trying to tell us that you will run out of vacuum too soon?