My 93 K1500 is shaking when I brake.

I noticed about 6 months ago the rotors seems to be warped. I would press the brake pedal and feel the pedal pulse when I apply pressure. Had the same thing happen on my Safari when the rotors warped. I would turn them down and it stopped.

I didn't get to the rotors on the truck because I stopped driving it for a bit. Over the last 2 months I started driving it daily and noticed the same pulsating was getting worse. I couldn't get to them turned right away and then over the last 3 weeks the front end started shaking every time I began braking at a speed of over 30mph. Under 30mph it wasn't that bad but I could still feel the pulse on the petal. I took the rotors in to be turned down by a guy I know does good work. The problem didn't change.

When I turned the rotors I also replaced the caliper pins. When I took off the rotors I checked the calipers to see if they were loose and they were not. I know I tightened them down when I put them back on.

The shaking doesn't seem to be side to side but more back and forth.
1. Tired out of balanced
2. Steering linkage bad somewhere
3. Roads have pot holes only where I brake each time

Any thoughts?

 

if its pulsing the pedal, its from the rear brakes.

apply only the ebrake when your at speed. do you hear the same thump noise?

 

My mechanic did say to change the rear seals on the brake cylinder. That might be why.

I'll start there. Tks tech2

 

machine or replace the drums while your at it