2004 screw fx4

Put front pads and rotors on today...truck was still hopping under heavy stoping....took it back apart and turned the new rotors ...they weren't true anymore ....back on witg what I know to be true rotors...still hopping...

Anyone ever run into this?

 

rotors should be true out of the box. are you sure you had them set up on the lathe right?

 

Yes. Without a doubt.

I never said they weren't true from the factory. They may have been but something keeps warping

 

Did you do the rears too? Also are you torquing the lugs down with a torque wrench?

 

No I didn't do rear. I would swear the hops coming from the front.

No I didn't use an impact gun. I used the tqwrench

 

Going to be doing mine tomorrow, same specs as yours. Hope I don't run into problems. Did you get quality parts? Lots of crappy cheap parts out there. If something is warping your rotors that quick I'd take a look at the calipers.

 

You stated it was still hopping under heavy brakeing after you installed new parts. did you properly bed the new lining [break in].if not there could be deposits on the new surface from improper beding it gives the impresion of a warped roter. Also is this a wheel hop or a pulsating pedel if its wheel hop check your shocks and look for loose suspension parts

 

I used Napa parts.

It is hopping. The pedal feels fine. Suspension wise is tight.

Like I said earlier...it's warping the rotors within having drove just a mile or so and back...

I'm clueless at this moment as to why

I have never seen rear disc brakes cause a bounce when stopping but I'm sure its possible.

 

What are the odds tires could cause this?

 

does the hopping seem to be coming from the front, rear, or both?

another thought i had is that sometimes you have rust build up between the rotor and hub. its always a good idea to use a wire brush to get as much of that surface rust off, otherwise when you put your rotor back on it may not be flush against the hub. we're talking thousandths of an inch here but you would definitely feel it. more so in the pedal though.