1998 Ford F150 Brakes grab at low speed

Have you removed the wheels to inspect the condition of the pads and shoes? Checked the calipers for frozen condition? Flex hoses cracked? Also checked the wheel bearings for looseness(play)?

Inspect the disc pads for contamination-such as brake fluid/grease/oil if okay could be the brake rotors badly scored and needs resurfacing

Thanks to all who submitted. We had just completed a brake job, so it was bewildering. We finally found it to be the brake booster, the only component left to check. The internal "apply" valve was failing and allowing full vacuum at idle. Problem solved.
Until next time.

Thanks for letting us know