1999 Tahoe, 4WD, ABS light & grabbing brakes

[hd_ryder]

What is typically the most common problem that would cause slow speed grabbing brakes, and an occasional ABS light coming on?

Would the ABS Wheel Speed Sensor be a good thing to look at?

Are the ABS Wheel Speed Sensors only located in the front on the '99 Tahoe?

Any affordable way to diagnose this system, or test the ABS Wheel Speed Sensor?

Thanks for the help.

 

[lesterl]

which wheel? Leaking caliper/ hose/ wheel cylinder........

The grabbing is causing one of the wheels to turn at a different rate than the others and is triggering the ABS light.