What would cause bonded brake lining to show cracks on every shoe after
about 10,000 miles?
Purchased the rear shoes from Napa about 2 years ago.
It starting squeaking almost from the start and today I pulled the drums
to check if I had metal to metal. The drums and lining look fine except for the cracks.
What gives ?????

 

Excessive heat would be my guess, i.e. driving like a Californian.

Panic stops will cause warped rotors in the front and bust up brake linings in the back.

 

What would cause the heat when I am not hard on brakes?

 

Do you tow a trailer or carry a heavy load? Use the brakes alot when coasting down hills (load or not, but esp. loaded)? This will build heat. Mile after mile in stop n' go traffic will do it because there is no airflow going through to cool stuff, so they never cool off before you have to use them again. A good example of the kind of traffic that does this is on CA-91 heading towards Riverside at 4 PM on any weekday.

 

I don't pull a trailer or pull heavy loads. Do have an auto,but down shift on long
grades
On the freeway I drive to the right at about 60MPH.

 

Also run B100 and try for max mileage with 3 speed auto. Don't have a lead foot.

 

Hmm, I dont know what to tell ya then. I know they used to do that on my Eagles all the time, but I used them on newspaper routes in high school so I know I was working the hell out he brake system.

When they started to squeal, I always pulled them apart and sprayed it all down with brake cleaner and then put plenty of brake quieter stuff on it and shoved it all back together. Granted, these were just little hairline cracks on the linings, not huge cracks and it didn't loosen any pieces up, so I never changed anything out. Of course, the Eagle didn't have a full floating axle, so it was just a matter of pulling the tire, undoing two drum bolts, spray it all off and shove it all back together. Aint that easy on the Dodge.

 

I put it back together with the fine cracks and the old seals. After driving it for about 5 miles, got under the rear to check if I had a seal leak, no problem

 

did ya ever leave the e-brake on just a little and not notice it until you started to smell it?

 

Had the e-brake on once for about a half block.
My computer has been down for the last day and a half, so I could not answer the last question.

 

hey! im a californian and i get passed by big rigs in the slow lane!

 

Yeah, that'll do it too! Big time. Not sure why I did not think of that... thats the most obvious.

This is true, but the difference is most semi drivers don't use exit only lanes (or the shoulder of the road, when no lane is handy) to pass you on the right or cut you off with inches to spare in high-speed traffic or turn right in front of you to get the exit on the immediate right and they just didn't wanna wait behind you for that extra fraction of a second.

 

I have to be careful of overheating my brakes when I drive in any kind of mountain driving.

Our A-727's freewheel as soon as you foot is off the throttle so there is no engine braking to slow you down.

Every time I am in the mountains there will always be some stupid small car in front of me that will keep riding his brakes all the way down to the bottom and keeps trying to crawl under my front bumper.

Wish there was a way to lock up my torque converter so I could have an exhaust brake.

When the truck is cold, try driving for a few miles and then get out and carefully feel your rear drums and see if they are excessively warm, if they are hot then something is dragging maybe parking brake or shoes not returning.

 

Lets assume the fine cracks are from overheating the shoes. Then what is causing the squeaking all the time? Is it hard lining or the material that it is made of?

 

I would assume that is it. The material gets a glaze over it that looks like and feels like black glass. I imagine its pretty hard and packed. Assuming you have checked over all of your hardware and made sure nothing is out of place/dragging, then its just the lining material on the drum. If you notice, semi and bus brakes sometimes sound like metal to metal even when the shoes are new. The driver got the brakes hot once recently is all that is. It will eventually wear off.

You might see if you can find a different braking material. Are these carbon metallic pads? If so, then that might have something to do with it, I always used carbon metallic on the Eagles and they seemed to like to do that. PFC Z-rated brakes are supposed to be the best for stopping (according to what I have heard), but what is best for you depends on a variety of things.

Also, could always make yourself a ceramic drum.