Another situation in Brakeville

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Here we go again. Traded in the 99 for a 01 because I wanted the 6 speed and the brake problems to go away. The 01 was great until I got a pulsation at 10,000 miles. Under warranty the rear drums were found to be out of round and replaced for nothing. Yeah! Now at 14,000 the pulsation is starting again. Front discs this time? Rear drums again? I've done the parking brake trip with no results. My driving habits are ultraconservative concerning stopping. About the only thing I've done recently was rotate the tires in the driveway and torqued to specs. Can it be the wheels? I'm at a loss. Helpful hints and experiences?

 

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46, do you feel the pulsation in the brake pedal itself or is it a seat-of-the-pants feeling?

Pulsations and vibrations are generally caused by runout(out of round)in the driveline. Because the tires, wheels and brakes are attached thereto, they must be eliminated from the equation starting with the most obvious and moving toward the least.

A surprising number of tire and/or wheel assemblies are out of round from the factory. I would check this first. Beyond that, I would return to the braking system. Radial (side to side) runout can be checked at any reputable auto shop using a dial indicated runout gauge. Heat buildup is the most common cause of rotor or drum warpage. Sticking caliper pistons, weak brake springs or a defective master cylinder proportioning valve can cause pad/shoe drag and the resulting heat in very short order.

If the pulsation occurs only while braking and can be felt in the pedal, the most likely culprit is probably rotor or drum runout. If it happens all the time and can be felt in the seat or steering wheel, it is probably tire balance or tire/wheel runout.

Hope this helps.

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'96 2500 x-cab, lotsa chrome, nerf bars, line-x, soft cover, no silencer ring, love to hear 'em bang

 

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Iron horse, Thanks for the great suggestions. I'll try the systematic approach that you advised.

 

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I have the same pulsating on my 2001 ETH 4x4. It feels like the rear brake drums to me but I haven't had the truck in yet. I can really feel it when I have the brakes applied lightly. Does yours feel like that too? Only got 2500 miles on it so far.

Pat

 

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Pat,

Sounds familiar. Get it in for a look and if the rear drums are the culprit get them replaced under warranty. Mine were out of round and noticeable at 10,000 miles