2019 yukon xl shake when breaks

[salisburyv]

OP hasn't been seen since posting this, apparently the issue is not that important. lol
it's almost always brake related when the problem happens while braking, shakes at speed are more likely to be alignment or tire/wheel related.

exactly!! i used to be a service writer. there were quite a few times (and it happened to me) where we would get rotors and they were already out of round(warped). so we'd have to give them a light cut to true them up. always with aftermarket you have to check run out on the rotors. i don't recall this problem with oem rotors.
it's usually always a bad rotor that causes a shake, could also be the mating surface between the rotor and hub, or rotor and wheel. let us know what you find out.