While driving on vacation with a truck load of bikes and camping gear, I noticed the brakes acting a little weird. Pulsing or vibration is probably the best description. Under normal load it's fine. Get the bikes on there (and I assume the LSPV kicks in) and it's back. My front brakes are 100% so I guess this sounds like rear brakes. When loaded like this the truck goes from a raked position to a little reverse raked.
Should I order up some new pads from Dan and then check the rotors for wear and just turn them if within spec? Obviously I'd order new rotors if they were out of spec.
Fortunately, they're about 20 mins a side to replace the entire rotor/drum assembly since they're simply held on by the wheel/lugnuts. Since this is true, I'd first try this:
Pull them off and hit them hard with some aggressive sandpaper using a circle motion. Be aggressive. Do the same to the pads though you don't have to rough them up much - just take off any shine. Use brake cleaner on the rotors BEFORE you put them on with clean hands (so you can clean both sides of the rotor). Reassemble and see if you eliminated it.
The reason I suggest this is that often a rotor simply has become mildly glazed or gotten a drip of road oil or something and it's pulsing because of different grip during the rotation rather than lateral runout. On a rear brake it's much more likely as they don't get abused like fronts do.
To check runout, you can use a dangerous method I've employed when nobody's looking. Put the truck on jackstands - all four wheels in the air. Remove the suspect wheel so you can get to the disc. Run the truck in gear and use a screwdriver braced against the caliper to see if you can get it to touch for only part of the revolution to guage runout. There's always a little of course. This is insanely stupid, but I've done it in frustration to isolate a warped rotor. Obviously anything you catch on the rotor (hair, sleeve, tool) is gonna get some serious damage so be sure to have a camera rolling so we can see it next year on TV....
I had some pulsing in my brakes a while back. It turned out to be the rear rotors. What had happened is that the e-brake had stuck on and heated them up enough to warp them. I was able to just rotate the wheel and hear it contact the pads every so often. To do this put the T-case in nuetral and spin the wheel with it lifted of the ground. Besure to chock the front wheels to stop the truck from rolling.
Rick - Were you able to fix the warped rotors by turning? or did you replace them?
Doug - Good idea on the glazing. Since I need to replace the axle seals as PM soon, I'll do the sanding thing and brake clean at the same time. I think I'll skip the runout test, I don't need the cruiser in my living room. :whoops:
My truck had over 100k and I decided to replace all the rotors and pads in one fell swoop. If they are out of round you could turn them if they are thick enough.
I heard somewhere about Dan being on vacation this week? I could order up some parts and have at it when I get home. Nothing like ending my vacation by working on the cruiser.
Riley, he was around yesterday when I called him for some parts. But it was hectic over there. If he's not around, you could always buy the stuff from John Hocker.
Not sure when your vacation is up, but remember, rotors are heavy so ground shipping is your best bet. Don't know if that means they'd get there after the vacation ended or not.
I heard somewhere about Dan being on vacation this week? I could order up some parts and have at it when I get home. Nothing like ending my vacation by working on the cruiser.
