Brake shudder

Hi, chevy express van with 14,050 gvwr dually chassis. 4 wheel abs disc brakes.
I overheated them coming down a mountain ( not enough to smoke em, but I could smell them for the last few minutes at the bottom of the grade)and am getting a slight pulsing in the brake. Not during slow speeds but slowing down from highway speeds or under a harder push on the brake. I don't remember if it did it before they overheated or not. I am not sure if it's the abs or a mildly warped rotor.

Can I tell if it's warped with a dial indicator while the rotor is on the truck? I have a mag mount for the indicator or can rig a solid mount - dial reads .001 -- or is there another way to check.

Does anyone know how much runout is allowed in specs for the rotor?

Thanks

Sometime warpage is hard to read.
If it is a rotor shake turn or replace them.
And be sure to torque wheel lug nuts when done.