What year Tahoe? Are you using a weight distribution hitch? If not, you need one. The Tahoe's suspension is soft and not the same as the 1500 series PUs. I would worry less about the rear squat than putting the weight back on the front wheels, which is what weight distribution does.
We had a '95 Suburban that we used to tow our old Kiwi 17a (ancestor to your 17Z) and we needed the WD hitch with the 'Burb.
2013 Jayco Jayfeather X20 E, 2008 GMC Sierra 1500 Crew Cab Z71 SLE