Shaking while med-hard braking.

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Dutch Rutter

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Hello everyone,

I have another annoying issue with the k20 and Im hoping for some guidance on where to start looking for the problem.

While applying medium to hard braking I get a pretty severe shake. This shake gets worse when headed downhill. I do not feel the steering going side to side nor do I notice any pulsing in the brake pedal. It feels more as if the body of the truck Is bouncing up and down rather harshly. It also feels as though it's on the passenger side.

Not too long ago I replaced the rotors, pads, and front wheel bearings. At that same time, I also replaced the rear drums and shoes. More recently I've replaced all of the leaf spring bushings, sway bar bushings, and shocks and I've recently had an alignment.

The truck does have a 2" lift by the previous owner, blocks in the rear and springs in the front.

Where should I start looking? I'm really drawing a blank.
 

eskimomann209

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Bad tie rod end will do that.
Could be sloppy ball joints
Just because a shop aligned it doesn’t mean they checked the tie rod ends either.
 

PrairieDrifter

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I would say warped rotor, you said you replaced them but you never know.
 

PrairieDrifter

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If the pads and shoes aren't seated (burned in) properly, this can happen.
Exactly what I was thinking, I've got a 98 2500 and it acts different all the time but i know the rotors are warped. Sometimes you feel it in the pedal, sometimes the steering, sometimes the body. Every now and then some symptoms at the same time, never consistent though.
 

Snoots

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Exactly what I was thinking, I've got a 98 2500 and it acts different all the time but i know the rotors are warped. Sometimes you feel it in the pedal, sometimes the steering, sometimes the body. Every now and then some symptoms at the same time, never consistent though.

If rotors are warped they must be replaced. I don't give a fat frogs fanny who tells you that you just need to have them turned, IT WON'T WORK!

Once the metal warps it is 'set'. There's no turning back.
 

eskimomann209

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The question is and this is how I read it. Does the shaking stop once he releases the brakes? if so then yes rotors / pads. If it persists. I say steering/ loose suspension.
 

Dutch Rutter

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The question is and this is how I read it. Does the shaking stop once he releases the brakes? if so then yes rotors / pads. If it persists. I say steering/ loose suspension.

Yes the shaking stops with brakes released or when I feather the pedal. Which is how I've been driving it lately. I'll try and get a quick video of it happening tonight after work, there is a hill that it always happens.

Edit: I did a test on the way in this morning. While driving I held the e brake release and applied even pressure to the emergency brake. Whatever is causing this shake is definitely in the rear end somewhere. I guess I'll be pulling apart those drums this weekend.
 
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Dmack

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I have heard of our of round brake drums.....
 

Snoots

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Hopefully his new drums aren't made of chineseium.
 

Dutch Rutter

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I have heard of our of round brake drums.....

It's possible that one of the new ones I put on had a high spot or something due to bad QC. Or I might have gotten something not put back together quite right.

Can you get the corona from chineseum metal???? Lol JK the ones I bought where a few years ago and from napa so.. maybe?

Here is the video I took. It sucks, but you can at least hear the rattling from the shake, I tried to get the brake pedal in there as well but didnt do so great.

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Craig Nedrow

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If you have an mag base and a dial indicator, you could actually see if they run out.
 

Craig Nedrow

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looks like this

You must be registered for see images attach
 

Octane

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New drums need turned before install in my experience.Rotors no.Ive bought new drums that were warped so bad that they would have to be turned to the max. diameter to get the warpage out.
 

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