2002 astro ls rwd rear drum brakes pulsate

[KIRK1967]

Changed everything and they are good for a little while then they just get so bad you cant drive the car .if anyone has any insite on this problem it would be greatly appreciated.

[chevymaher]

Check the rotors. Specifically the inside. Mine looked great when you took the wheel off. But inside under the dust cover where you can't see easily. Warped, chunks gone from the hardened metal. I replaced everything at once. Brake pads, rotors, drums. Case closed problem solved for me.

[KIRK1967]

What do the front rotors have to do with the rear drums warping?

[chevymaher]

It is what you don't check when you miss things.

If your sure it the rear drums. I would say the shoes are not retracting correctly. Causing heat build up.

[Phantom]

What do the front rotors have to do with the rear drums warping?

Drums are not the items known for warping ,, rotors are , they can be out of round , but when the shoes are adjusted out too far they can give a pulsating feel since the shoes are not retracting as they should ,, also there are cases when a diy'r will put the shoes on backwards or the 2 larger shoes on one wheel and the 2 smaller shoes on the other wheel when there should be one of each on each wheel,

double check they are installed correctly and adjust them in a little bit

[KIRK1967]

The shoes are on correctly and all the hardware has been replaced and there was no drag when adjusted the drums get warped or you could say out of round .i replaced the drums twice the second time with new shoes.and it will be almost fine even with the new drums they are not perfect,the new drums out of the box are not good they had a little pulsation to start but i could deal with a little but not when it shakes the whole truck.

[Jasen]

Makes me wonder how a drum is warped right out of the box. I mean they are turned in the mfg process. I've never run into that, but I haven't replaced drums sense back when they were common on cars and were at least made in Mexico. Cheap Chinese drums maybe? I suppose if the turning spindle is out of whack, that would give a out of round turning, which leads me back to China.

But once they start or are already warped, they don't get any better.

[chevymaher]

Just a passing thought as I was cruising the post. Take your drum off and wiggle the axle see if there bearing play. I had that, and it messed with the way mine was braking.

[KIRK1967]

What about the hcu not purportioning properly

[chevymaher]

What about the hcu not purportioning properly

Possible. My anti-lock brakes used to go crazy all the time.

[KIRK1967]

I had it on the lift the other day at work and checked for play but i didnt notice any.someone else told me to check that also,

[Love my chevy]

Hi all, just joined this forum i think its great. I have a 97 astro and having the same problem. Im not a mechanic but i do my own work when i can. I did all the same things you did no luck. Then i got lucky i checked my backing plates and there is two gashes in the bottom of the plate. The break shoes are getting stuck in the gashes . this is very dangerous. I will have to change them. This maybe your problem so check it out. Good Luck

[Ragenme]

It's sounds like the rear shoes are over adjusted. Will the drum come off with ease or do you have to beat on it? I've seen this before. Adjust the shoes down a bit and test drive it. See if your shake goes away. Start simple and work your way into it! Hope this is helpful.

[KIRK1967]

I had already done that,i left them loose and it still happened

[DRZ]

A little off this subject but the one thing I notice behind the wheel when getting from my 2000 Astro "El" into my 2004 Cargo is the 2000 brakes seem normal as I've driven Astros since my 1st new one in 1987 but when I get in the 2004 the 1st time again and I hit the brakes it seems like I'm about to bounce my nose off the steering wheel as the 4 wheel larger disc brakes are that much better.