Mike Perez

Occliffie,
Sorry to hear that the MAP sensor didn't fix the problem.

The wheel cylinders take some time, but I take the time to clean all the parts ( wire wheel the rust off all mechanical parts) and lubricate all contact points. I'm not sure if the stock cylinders are under sized for the truck, I have a few friends that have the 1999 4x4 diesel and thier cylinders all leaked. The shoes on my truck had almost no wear compared with the new ones I purchased.

I found the number off the DTR site---GM one Ton #4637337 just give them the number at the auto parts store. I think they were $16.00 each. I took a picture of the brakes with my wife's digital camera prior to breaking the brakes down, that way you can look at the picture.
You only need to bleed the rears, unless you let the brake fluid get low inside the master cylinder, so don't let that happen.

Again, I found this idea on the DTR site, "removing the rear drums". Put your truck on jack stands and remove your wheels, if there are any retaining clips on your lugs remove those too.
Put a couple lug nuts on each hub, leaving a half inch before snug then start your engine ,
eccelerate in reverse and slam on the brakes. This broke both drums free, you may need to retract your shoes to remove the drums. ( The lug nuts are on so the drums don't roll away)

If you are only going to exchange the cylinders you can remove the springs at the top to access the cylinders.

Good luck, MP

ryanofire

ocliffie,

Ordered the map sensor today will pick it up in the morning and attempt to install. I hope it go's as well as tool's replacement went. One more question and this goes out to really anyone. Why is it that dealerships will have no part in listening to your suggestion's when it comes to trying to figure out problems? I told them that I had done a lot of research on my problem and they looked at me like I was crazy. Oh and they didn't even want to hear of this site. But that's okay because I politely explained I have received more help on this site than they could ever start to give me in the near or far future.

ocliffie

Here's the latest

Changed the overflow checkvalve this weekend. drove five miles and was ready to celebrate and crack open a cold one and then bam, back to the normal problem. Code is 0216- injection timing control circuit malfunction, fuel injection pump timing failure

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