Once Agian 1999 24v 3500 Dually I Have Replaced The Fron Rotors And Pads 3 Times In 9 Months. They Only Last About A Month Then They Start Shaking Very Bad When I Apply Brakes And I Cannot Hit The Brakes To Hard Or They Will Almost Completely Lock Up And Act Like The Abs Isnt Working.

 

Sounds like you've got a hanging caliper. Advance autoparts house brand of rotors will warp in weeks. Also , what pad are you using? We never use gold or platinum pads (how ever your parts house words it) on new rotors, It will build to much heat and warp. are you putting a cross directional pattern on the rotors when you install them?

 

When you first install these rotors you need to measure runout as soon as they are installed on the truck. With this style of hub that requires the studs to be pressed through the rotor, it is quite common to have excessive runout right from the beginning, and it seems to make no difference how fussy you are during installation. The only really dependable way to machine the rotors on these trucks is with an on-car lathe, as the hub can't be set up perfectly true on a bench-style lathe. I recommend you have this done when you install your next set of rotors, and see how much difference it makes to the lifespan of the rotors.

 

my diesel mechanic mentioned the on car lathe and also told me something about the breaks having to do with vaccum system as well. so i am hoping that i am having a vaccum issue. (like the one in the other post i sent about blow by)
my symptoms include: 4 wheel drive not working, cruise control not working, and heater stuck in defrost mode.

 

Maybe they need some help from the rear brakes. Very common to have frozen self adjusters.

 

4WD, cruise, and AC in defrost = unhooked vacuum line! Check the firewall on the driver's side for a loose line.

 

yup! there was a crack in one of the elbows in my vacuum system. gonna check and see if my 4x4 and cruise works when i pick it up.

 

You do not have vacuum assisted brakes. You have hydroboost assisted brakes. On brake wear, you must not have any rear brake function or you have more abuse than I can imagine. You have surely replaced the front calipers at some time I assume and both fronts are wearing out together.

 

my rear brakes were hardly working even though I would keep them adjusted,had a friend that worked at a dodge dealer that said there was an internal memo that said to replace the height valve for the rear brakes with a hose {I don't remember the part #} but now I've got good brake pressure at the rear and the front brakes last twice as long.