Are the brakes on the 89-93 Dodge Cummins trucks powered by via hydroboost or by vacuum? My 89 Cummins powered Suburban is using its OE vacuum operated brakes using vacuum supplied by the vacuum pump on the Cummins engine. The issue I'm having with the brakes is that they are woefully inadequate for slowing down this 7000 lb. beast. There is no issue slowing down at a normal rate but if I need to slow down at a brisk rate, I have to literally stand on the brakes and count to 10. The brakes don’t come even close to locking up even when standing on the brakes. I’m starting to wonder if the issue is that the vacuum pump is inadequate for powering the vacuum booster on my truck. If that’s the case, either I should install a reservoir or switch over to a hydroboost system. If I switch to hydroboost, is there a port on the power steering pump to power the hydroboost?

 

 

Start of by checking for vacuum leaks to make sure you are not trying to blow up a ballon with a hole in it. Then check the vacuum pump for the ability to draw enough vacuum to make the brake booster deliver proper braking power. If the rest have checked out test the brake booster (broken diaphram or vacuum leak). Now that you are satisfied that all the above is in good working order look at the brakes themselves. El cheapo pads and shoe material will just not deliver a good stopping distance. Besides when all is said and done you will be able to relax your sphincter muscles and smooth out the wrinkles in your seat cover. If you know someone who has a 12 volt vacuum pump you can borrow to help test the system it would save you some time. A few lessons from Fred Flintstone might help.

 

Do your trucks use a vacuum brake booster or hydroboost setup?

If it's a vacuum setup, do they have a vacuum reservoir?

I'm asking because maybe all I need is a reservoir.

 

no they do not and yes there vacuum

 

its easy to convert to hydroboost. ask me how i know

 

 

Please let me know your experience converting to hydroboost. I'm planning to buy a complete hydroboost unit which includes the power steering pump off a newer body style 1988 Chevy truck. The question is if the Dodge power steering pump is up to the task to run the hydroboost or I have to find a way to adapt the Chevy power steering pump to the Cummins engine.

 

bump

 

Sorry, but it sounds like you've already decided to convert to the Chebby H-boost system, so I can't help troubleshoot the Dodge vacuum system.