Question about vibration

[asshanson]

Whenever I brake from say 40mph to stop, I sometimes get this weird lurching. Not all the time, but sometimes it'll rock front to back, like I'm pulsing the brake pedal. Normally I'd say something is wrong with my brakes, but sometimes it even does it when I'm coasting from 10mph to 0, lurching slightly. I've also noticed that instead of coming to a really gradual stop, it sometimes will stop like I've barely touched the brakes and won't roll backwards on a very slight uphill, like there is friction somewhere. Could this be from a really warped rotor or a bad axle?

Oh yea, and I'm getting some slight vibration under acceleration from 3-4k rpm that started happening recently as well.

Last winter I heard tiny click sounds coming from the front passenger axle I think while at full turn, maybe it's finally going out. Last week I also heard this weird grinding sound for a second and it went away, I never did figure that one out. Also when I brake and I'm next to a wall on the passenger side with window open I can sometimes hear a cyclical noise. I guess I should just take off both passenger side tires and inspect the brakes, but I'm not sure what to look for.

Can I do a simple test myself to see if they're warped or do I have to take them somewhere? They're powerslot rotors and r4s pads are both around a year old, maybe 10k miles, I wouldn't expect them to be bad already. How can I test if I have a bad axle?

[A//// Guy]

I bet one or more of your calipers are seized up and are not releasing. I just rebuilt my front calipers on my car.

Jack up the car and spin each wheel and see if one is tougher than the rest. They should spin freely. It could also be your parking brake sticking.

[asshanson]

Sweet, thanks. I already have rebuild kits for all four, I was going to do that when I repainted them black this summer. I may have to ask you for help when I do the rebuilds.

[Kevin 1G Drummer]

Judging by your pulsating at low speed braking, I'd say one or more of your rotors are warped.

[b00stcreep21]

My money is on warped rotors caused from siezed caliper(s)