96 ford ranger XLT front brakes pulsate

[Ranger850]

I replaced the front pads a few months ago with NAPA semi-metallics. Brakes were fine for a few days then they started to pulse a little and it got worse. I took the wheels off this weekend and cleaned up the rust on the steel wheel hub and back of the aluminum alloy wheel and re-installed. I've never done this before on any car but I read that it might help. I used a wire brush followed by a Scotchbrite pad on the steel and just the Scotchbrite pad on the aluminum. I followed up wit ha very light coat of high temp brake grease on the areas I just cleaned up.

Afterwards I was very careful about torquing the wheels - first to finger tight, then to 50 ft-lbs on the jack stands in a star pattern. Then I lowered the car and torqued them to spec (100 ft-lbs) in star pattern on the ground.

On the test drive the pulsing was almost gone. Now after driving the car 3 days its back and getting worse - just like before. What could be causing this that removing the wheel and putting it back on improves for a few days? Everything except the pads is original (22 year old) stock parts. Not sure what to try next other than bleeding the brakes.

Did it pulse BEFORE you slapped pads in it?

 

[Uncle Gump]

Who had too much coffee?

Well you deleted your post... so whatever makes you happy.

 

[Uncle Gump]

Warped Rotors cause the steering wheel to wiggle, drums cause pedal movement. I worked in a brake shop for 3 or 4 years and have seen a lot. That's why I was asking what is pulsating. Vocabulary is getting blurry. Pulsate or vibrate or wiggle. To Me - all are different, and are different symptoms for different problems.
the fact that it went away by cleaning them and then came back, does not say " Warped" to me. I have also turned many a rotor and drum in my day. that's why I was looking for clarity on the vocabulary here.
That's why I mentioned the booster, there are other thing that cause "pulsing" besides warped rotors/drums.

I guess we will have to agree to disagree... arguing on the internet is pointless.

But the fact remains... warped rotors will without a doubt cause the pedal to pulsate... period.

 

[adsm08]

Warped Rotors cause the steering wheel to wiggle, drums cause pedal movement. I worked in a brake shop for 3 or 4 years and have seen a lot. That's why I was asking what is pulsating. Vocabulary is getting blurry. Pulsate or vibrate or wiggle. To Me - all are different, and are different symptoms for different problems.
the fact that it went away by cleaning them and then came back, does not say " Warped" to me. I have also turned many a rotor and drum in my day. that's why I was looking for clarity on the vocabulary here.
That's why I mentioned the booster, there are other thing that cause "pulsing" besides warped rotors/drums.

I'll agree this one is weird. Anything felt through the steering or not is more about front vs rear brakes than it is drums vs rotors, but I'm sure most of us knew that.

I have had rotors, on both ends, that caused a nasty pedal pulse. I even had once that once it got going you couldn't keep your foot on the brake pedal. The customer had no idea anything was wrong with his brakes.

I had another one, one time, where the on-car lathe didn't comp out correctly (it said it did, but it didn't) and caused a vibration that would come and go.

Somewhat off topic, but I have even had a tire vibration in one of my own vehicles that seemed to be caused by both front tires being in the correct "phase" to each other, because it would only happen between 55 and 65 MPH, but would come and go as I went through turns. It was almost as if the out of balance spot on each tire didn't hit the road at exactly the same time the vibration didn't happen.

 

[Ranger850]

Here is a test for warped rotors - Get the truck up to about 20mph, let go of the wheel and press the brake pedal, if the truck turns or the steering wheel wiggles, it is your front rotors, no doubt. but if the pedal moves up and down, but the truck stays in a straight line, it is likely, not the front rotors.
OP said "brakes started to pulse" after he put new pads in and "pulsing" started a few days later, he cleaned them, it went away and then came back. No way in hell he cleaned off the "warp"
pulsating is "usually" associated with bad rotors, but in this case it comes and goes with a wire brush cleaning.??? Sometimes the easiest fix isn't always the right fix.

Who knows, maybe I'm overthinking it,

 

[adsm08]

Here is a test for warped rotors - Get the truck up to about 20mph, let go of the wheel and press the brake pedal, if the truck turns or the steering wheel wiggles, it is your front rotors, no doubt. but if the pedal moves up and down, but the truck stays in a straight line, it is likely, not the front rotors.
OP said "brakes started to pulse" after he put new pads in and "pulsing" started a few days later, he cleaned them, it went away and then came back. No way in hell he cleaned off the "warp"
pulsating is "usually" associated with bad rotors, but in this case it comes and goes with a wire brush cleaning.??? Sometimes the easiest fix isn't always the right fix.

Who knows, maybe I'm overthinking it,

My experience suggests that both rotors may be slightly warped, possibly not enough to really notice individually, but that this is a "phase" issue, and both high spots need to hit close to each other before it really gets going. So going through a turn moves the two high spots in relation to each other, and makes it less noticable. That would explain why it seems to come and go.

I am still voting for replacing the 20 year old rotors and then re-evaluating the concern.

 

[98v70dad]

Is the pedal pulsating up and down, or is the car pulsating when you apply pressure to the brake.
If the pedal is going up and down it is NOT your rotors.
Warped rotors will cause the car to pulse, but if your pedal pulses, it is you Booster or rear drums.
The fact that is goes away and comes back after a few days is weird, because "warp" does not do that.

I can feel it at the pedal and sort of all over except I don't feel it through the steering wheel. At 70 mph the pulse is like a machine gun in frequency. I never said it goes away and comes back in a few days. I said I cleaned the back side of the wheel and the mating surface on the the rotor (flat area around the lugs) - not the rotor. The pulse went away for a few days after the clean up and removing the wheels and now its back. It doesn't randomly come and go.

 

[Ranger850]

I can feel it at the pedal and sort of all over except I don't feel it through the steering wheel. At 70 mph the pulse is like a machine gun in frequency. I never said it goes away and comes back in a few days. I said I cleaned the back side of the wheel and the mating surface on the the rotor (flat area around the lugs) - not the rotor. The pulse went away for a few days after the clean up and removing the wheels and now its back. It doesn't randomly come and go.

Correct: I wasn't saying it comes and goes randomly. I meant it went away after you cleaned the hat, then it came back a few days later. Warp does not go away. Unless like adsm08 is saying is true and Now that you said you feel it in the whole truck, it could be Warp.

 

[adsm08]

I can feel it at the pedal and sort of all over except I don't feel it through the steering wheel. At 70 mph the pulse is like a machine gun in frequency. I never said it goes away and comes back in a few days. I said I cleaned the back side of the wheel and the mating surface on the the rotor (flat area around the lugs) - not the rotor. The pulse went away for a few days after the clean up and removing the wheels and now its back. It doesn't randomly come and go.

Do the steering wheel test, even though you don't feel it in the wheel.

Get it up to speed on a nice open stretch of road, preferably with no other cars around. Then let go of the wheel, but keep your hands hovering right there so you can grab it quick if you need to. Then gently start to apply the brakes. If the wheel starts to shake back and forth replace your rotors. If it doesn't, and you still get the shaking in the truck, replace your rear brakes, including drums.

 

[Uncle Gump]

I' gonna just stay out of the wiggle wobble pull pulse debate...

I think adsm hit the nail on the with post 2... the truck is 22 years old and never had the rotors off... who knows whats going on with the bearings.

Do yourself a favor... Pull the rotors off...have them machined... clean inspect and repack the wheel bearings... replace the wheel seals... then give them a proper adjustment. I would probably put new pads too. If the calipers compress fine... clean and lube em up and reuse them.

Then take it on a test drive...

You have a 22 year old 50k mile truck that was your dads right... it's worth every penny, hour of time and skinned up knuckle you invest.

 

[Ranger850]

I' gonna just stay out of the wiggle wobble pull pulse debate....

"Ask your lady friend to wiggle it, then shake it, then pull it, then make it pulse, and I guarantee she will do something different every time." -Jake.

Jake was my boss at the brake shop, and that is what he said when I asked the difference in a shake and pulsating.

...and yea I worked at "Jake's Brakes"

R.I.P. Jake