Katoner

I have been getting an intermittent shake when pushing brakes, and driving around 60, figured since it doesn't happen always it must be a caliper (Seems the shake appears more when the truck is warmed up). Pulls to the left when I brake also..

Yesterday I replaced pads pins and caliper spring.. was fine at first then I felt it again upon braking. Calipers seemed fine when I retracted the Pistons using channel locks it was pretty smooth.

Wouldnt i get a constant shake upon braking if a rotor was warped?

Thanks

(1990 4r 22re 5sp 4x4)

Paul22RE

Is left wheel hotter than right after a ride? A bad hose can also cause caliper to stick.

Katoner

Didn't think of that, will keep an eye on heat and Google around to figure out how to diagnose a bad brake hose. I did notice a slight tapered wear on pads but only about 2 millimeters left to right

Katoner

Can the brake booster system cause something like this? I notice my brake pedal going spongier and harder again every now and then, maybe unrelated? or maybe the pedal is also due to the brake issue and not the brake booster?

akwheeler

First off, do you feel the vibration in the seat of your pants or does the steering wheel shake?
if you feel the vibration through the seat before the steering wheel shakes you have a problem in the rear not the front.
to confirm this you could lightly apply the parking brake which applies the rear brakes only. if you feel the vibration your rear drums are warped.
this doesn't mean that there isn't an issue with the front also, just that there is definitely a problem in the rear.
you can get a pull from the rear brakes also, it is just not as common or pronounced as an issue from the front.
When you feel the vibration does it continue every time you hit the brakes and go away only after you have stopped driving and everything cools down?
When you feel the shake pull over and check all 4 wheels for heat, see if any are hotter than the others.
Jack up your truck and roll the tires by hand, any of them dragging?

akwheeler

Maybe, it could be from excessive heat from a brake dragging causing the fluid to boil (especially if it is very old fluid).
For the best most consistent pedal feel you need to be sure your rear brakes (including the parking brake) are adjusted properly and that there are no other brake system issues before you condemn the booster.
make sure to check your hoses at each wheel and at the rear axle for blisters/cracks or other damage. you can't check inside for a collapsed liner but that would cause a brake to either not work or to not release.

Katoner

Upon braking it's more of a front/back pumping than a side to side vibration, like if it was intermittently grabbing the disk (or drum). And steering pulls left pretty hard.
on freeway however it's a shake, in the steering.

Will check drag this morning and take a good look at all hoses

I put a lot of work on this truck when I got it a year ago (HG, leaks all over the place, tranny, and well its my DD since..), it was poorly maintained i wouldnt be surprised if fluid is really old..

Katoner

raised the truck.
no cracks or swelling on brake lines.
no significant wheel drag either side, and when pushing brake pedal slowly at different pressures the drag increases both sides the same so Im guessing no internal issues in my brake lines?

no pumping when using only parking brake so issue is in the front most likely.

my suspension components have been replaced, no wheel movement with truck raised. truck drives straight and handles like it should minus that shake at 65 and on.

warped rotor?

Kolton5543

Do you feel the pedal pushing back at the same time?warped rotors will usually force back the pedal and will shake anytime you brake. It sounds to me like you have a glazed spot on the rotors. Causes only a hard grab or loss of grab when in a certain temperature range. This is usually caused by hard braking that build a lot of heat, then coming to a stop and sitting.

Paul22RE

Hoses may look fine on the outside, but can collapse on the inside causing the caliper to stick. Problem will get worse as fluid heats up since hose gets hotter and collapses even easier.

Katoner

Well new development I feel the pedal slightly sinking deeper and deeper when stopped at red lights.., so after all it's probably my master cylinder on its way out..
did some research on the board couldnt find a proper "how to" but will keep looking. I did see a lot of talks about the "upgraded" MC.. mine has a "1" stamped on the side does that mean it's a 1" bore MC? Anyone know a part number (s) for this MC plz? Thanks

amamike91

I once had a shaking in the front end when braking. Mine turned out to be the steering dampener was bad. Changed it and it went away.