Brake Shake....

[Diver88]

Have you had the rear drums off at all to inspect their condition?

Yes replaced the drums and shoes at 210,000 miles when a rear wheel bearing seal went bad, never had been replaced up to that point and the shoes weren't worn completely out, but needed replaced anyway. Looked yesterday to see if the wheel cylinders were still dry, and they were. I've used the parking brake alone at slow speed to see if that might be causing an issue but they stop fine with no bounce . Thanks

 

[Diver88]

I noticed you said “rotors and pads”, but no mention of calipers being replaced. Have they been checked or serviced? To RichLo’s point, you could try just stepping on parking brake to isolate rear brakes. Many new parts suk too, what parts are you using?

I've been told that the pads are wearing evenly with no sign of a caliper sticking, so no no-one has ever replaced or serviced the calipers. Isolated the rear, no "bouncing" with just the rears. Parts I'm sure were all over the place, I saw the boxes for the rotors after one changeout (marked BRAZIL) and called the parts store I knew where they got them and they told me they were the cheapest parts you could buy. Next change out was Raybestos, don't know about all but the last time they were all Wagner.

 

[garet]

All you have to do is inspect their condition

 

[Caman96]

I replaced original drums on my 03 Tacoma recently along with new spring kit and shoes. Thump thump thump, so RockAuto sent out replacements. Same thing, sent them back for refund and put originals back on. Smooth as glass. Both Raysbestos drum pairs were out of round and out of balance. China shiiit.

 

[1998_K1500_Sub]

A bad hose, resulting in caliper drag?

Corrosion on a piston, <ditto>?

I’ve had a rotor “turned” on a shop’s lathe and measure 10 thousandths runout on the hub; with a new rotor, same day, same hub, I got 2 thousandths (which IIRC is the service manual spec). I tried reclocking the 10-thou rotor on the hub but still got 10 thou runout.

Don’t trust all brake lathes, or new rotors for that matter, trust your dial caliper.

Same 10-thou rotor would sometimes brake smoothly, sometimes not.

There’s a reason for a runout spec.

 

[Diver88]

Does the shake happen in the steering wheel? Or mostly in the seat/floor? ABS light on when it happens?

Stock suspension and tires? Towing heavy often?

Could be my comprehension skills but are you saying the shaking happens under braking regardless of how new the brakes are or only after a few thousand miles? So it still shakes when pads and rotors are new?

I wouldn’t say bedding is nonsense, it does serve a purpose.

As @Caman96 questioned, what parts are you using? A lot of new brake rotors are garbage that warp easily because they are made from inferior materials and there is t as much material in them to properly dissipate heat.

OK, no I don't really feel it in the steering wheel or the pedal (pedal hard to tell with it bouncing), no ABS light, ABS does work well... it activates fine, DFW drivers.
Seems like it takes a few thousand to start up, not just changed. The front of the truck just bounces up and down coming to a stop. All stock suspension with new stock replacement premium Gabriel shocks 6K miles ago, Michelin LTX M/S tires. Thanks

 

[Diver88]

Is the front end "bouncing up and down" when you apply the brakes or is it vibrating? I suspect the latter, which is a common symptom of warped rotors. All of the new rotors I have acquired made from Chinesium did this to some degree, and very quickly after installation. I considered machining some from solid steel but don't have a lathe with sufficient swing to pull it off.

It's actually bouncing from 10-15mph to stop. It does feel like its catching on something making the bounce, like it's hitting a sticky spot as it rotates. Checking
run-out shows nearly perfect on both rotors. One person suggests it's the semi-metallic pads depositing material on the rotor after a high speed stop and hold on the brakes waiting for a red light. This is the only thing that resonates with me but can this be fixed? Like I said in the original post, I've have driven lots of cars, have 3 others in the driveway now and have not had this problem with any of them. ??? Thanks

 

[Supercharged111]

It's actually bouncing from 10-15mph to stop. It does feel like its catching on something making the bounce, like it's hitting a sticky spot as it rotates. Checking
run-out shows nearly perfect on both rotors. One person suggests it's the semi-metallic pads depositing material on the rotor after a high speed stop and hold on the brakes waiting for a red light. This is the only thing that resonates with me but can this be fixed? Like I said in the original post, I've have driven lots of cars, have 3 others in the driveway now and have not had this problem with any of them. ??? Thanks

Go back and re-read my post. Based on what you're describing, it sounds like rotor deposits.

 

[Diver88]

1. Multiple sets of pads, multiple sets of rotors, same problem. I was thinking that It's probably not the front brakes, until you mentioned that using the brakes "hard" fixed the problem temporarily. Are you one of those drivers that brakes gently for a block-and-a-half before each stop sign? That's poor practice.

2. Might be the rear brakes. Test with park brake as described previously. Pray that the park brake cables aren't seized.

3. Bounces up and down? How old are the shock absorbers?

4. How old are the tie rod ends, ball joints, control arm bushings, idler arm, Pitman arm...is braking force moving the worn-out suspension/steering parts in a way that affects wheel alignment?

No, I don't ride the brakes, my Wife will tell that I wait till the last second to stop. Again, 0 issues with the original brakes until 90K when replacement parts were installed. Tested using the Parking Brake, no bounce, PB works well. Shocks replaced recently, decent quality I assume. I had the outer tie rod ends, Idler, pittman arm replaced 10K ago, nothing seems loose but original ball joints and bushings could stand to be replaced because of time I suppose. Wheel alignment shows good, tires wear evenly with no cupping or feathering. I did think about a belt slip but after rotation nothing changes and I can't see the hard braking making a tire better,
and it rides slick as glass on the highway, and everywhere else if the brakes aren't applied. Thanks, everybody has been making really good suggestions.

 

[Keeper]

how old are all 3 brake hoses? especially rear