I have a copy of the Chevrolet 2020 Trailering Guide. It is too large for the Forum to allow me to upload it. If you PM me your email address, I will email it to you.
The Max Trailering package does not change the GVWR (Gross Vehicle Weight Rating) of a Tahoe. What it does is change the GCWR (Gross Combined Weight Rating) of a Tahoe and a trailer. Without the Max Trailering Package the Tahoe GCWR is 12,000 pounds. With the Max Trailering Package, the GCWR is 14,000 pounds, which gives an additional 2,000 pounds of trailer that can be towed. Note that in the "Notes..." below from the Trailering Guide, any Tahoe with the "...standard Heavy-Duty Trailering Package includes an auxiliary external transmission fluid cooler and engine oil cooler."
As you noted in your June 18 post on your VIN RPO sheet, you already have the
"KC4 - ENGINE OIL COOLING SYSTEM,
KNP - HD AUX TRANS. COOLING SYS
My 2016 LT with the NHT Max Trailering Package has the exact same KC4 and KNP cooling packages. On my 2016, the Max Trailering Package RPO code is NHT. Perhaps Chevrolet changed the Max Trailering Package RPO code to MHT between 2016 and 2020. I don't know.
Your current Front and Rear axle gross weight ratings should be on a placard on your door jamb along with your tire sizes and tire pressures to achieve your GVWR and Gross Axle Ratings. It should resemble this. My placard is down low on the pillar between the left front and left rear door openings.
Interestingly, the NHT Max Trailering Package required the 18X8.5 Wheels and P265/65R18 tires in 2016 and 2018. Don't know about 2020.
For what it is worth, I have a copy of a 2018 Tahoe Order Guide. It states that the Max Trailering Package requires the two speed transfer case on 4WD Tahoes. I don't know if the two speed transfer case is rated for more power than the single speed transfer case. The low setting on the two speed transfer case would help pull a heavy boat and trailer up a steep boat ramp.
You can add manually adjusted air bags from the AirLift company
https://www.airliftcompany.com/ in the rear suspension coil springs or add air shocks and run the inflation air lines to a tire type air valve fitting near the trailer hitch. That used to be done all the time until the factories realized they could charge bucks for installing an on board air compressor and air shocks with automated leveling. If you wish, you can pay more bucks to get an onboard air compressor.
According to AirLift, their air bags do
not increase the load capacity (GVWR) of a vehicle. They don't make a three-quarter ton vehicle out of a one-half ton vehicle. They only provide a means for leveling the vehicle when loaded, so the headlights don't point up in the sky and blind oncoming drivers with your low beams. It also raises the rear end up so that it is in the center of its range of motion.
You can have a shop add an aftermarket trailer brake controller. Used to be done all the time. Still done when the factory hasn't installed one.
You can put the 3.42 axle ratio in your front and rear axles. Or, you can just run your transmission in Tow Haul mode and the M5 gear selection when towing. Unless you are pulling a 6400 pound boat and trailer up a steep boat ramp, you should have no problem.
The following two paragraphs are a cut and paste from the 2020 Trailering Guide. The first paragraph is a neat table with columns in the Guide. The formating gets lost with the cut and paste. But the info is there.
Taho 2 = Tahoe 2WD
Burb 2 = Suburban 2WD
Taho 4 = Tahoe 4WD
Burb 4 = Suburban 4WD
SUBURBAN/TAHOE TRAILER WEIGHT RATINGS (LBS.)
ENGINE | AXLE RATIO -| GCWR | Taho 2 | Burb 2 | Taho 4 | Burb 4
EcoTec3 5.3L V8 with Max Trailering Package
-=-=-=-=-=-=-= 3.42 | 14,000 | 8,600 | 8,300 | 8,400 | 8,000
EcoTec3 5.3L V8 | 3.08 | 12,000 | 6,600 | 6,300 | 6,400 | 6,000
EcoTec3 6.2L V8 | 3.23 | 14,000 | 8,400 | 8,100 | 8,100 | 7,900
When using a weight-carrying hitch, the maximum trailer weight is 5,000 lbs. with a 600-lb. trailer tongue weight. A weight-distributing hitch and sway control are required for trailer tongue weights greater than 600 lbs.
Notes on Suburban and Tahoe: Trailer tongue weight should be 10% to 15% of total loaded trailer weight (up to 1,000 lbs.). Addition of trailer tongue weight must not cause vehicle weights to exceed Rear Gross Axle Weight Rating (RGAWR) or Gross Vehicle Weight Rating (GVWR). The standard Heavy-Duty Trailering Package on Suburban and Tahoe includes an auxiliary external transmission fluid cooler and engine oil cooler.
