i had warped rotors in the front and my steering wheel shook. more at some speeds than others. went away when i changed them. i dont think i felt anything in the pedal.
if the rotors are warped. you would feel the shake
in the wheel when braking. According to your description.
You are driving at low speed no brakes applied. you feel
a pulsation. I would suggest a tire or balance problem.
try rotating your tires to see if the problem moves. also
make sure your tires are correctly inflated. also that the
wheels and tires are matched for that vehicle.
since new till 220,000 miles i would surly think the brakes and tires have been changed since then. are you talking about a forward type of surge? where it feels like you just got a small push forward over and over?
Based on your description you may have an issue with ‘hub runout’ meaning the hub rotor attaches to is not true. There is a way to correct this and test this theory and that’s to have the rotors machined on the truck, do this and it will eliminate any hub runout issues you might be dealing with.
Keep in mind it could also be coming from the rear, you may have an issue with the rear brakes causing the problem.