Was getting close (inside 500lbs) to my rear axle rating of 6,200lbs on my 2017 gmc 2500 when fully loaded with passengers, cargo, tools, camper shell, roof top tent, 30’ airstream with propride, water, dogs
Etc.... truck was handling it no problem whatsoever but did not leave for very much suspension travel on the rear axle with the ~3” of squat under heavy but acceptable load (still within all my GAWR limits. Note that these trucks have a lot of rear-end rake, so 3” of squat has the truck essentially sitting dead level vs nose high.
Weight distribution on the propride is great and front axle is 50+% restored (heavy duramax helps keep the front end pinned to the ground too) but I wanted to restore some of the travel on the rear end + keep the headlights on the road a little better.
Note that the only engineering difference between the 2500 and 3500 SRW Duramax on the 2017 MY are higher rated rims, tires and a helper spring on the 1-ton rear axle which provides for another 800lbs of payload or door sticker rear axle rating of 7,000 lbs up from 6,200lbs. Everything else is identical from front to back.
I had already upgraded my tires which are now rated for 7,500 lbs per pair @80psi and threw on some 1-ton spec rated gmc factory rims for good measure. Plus they look better
Went back and forth on adding a helper spring on the rear but in the end decided to go with air bags from air lift instead. Model 88338.
Happy I did, install went smoothly and I can now fine tune the ride quality, sag and suspension travel. Not to mention load up the rear end to 6,200lbs and not bat an eyelash given the equipment I am now running.
Fully aware that legally the door sticker rear axle weight rating is unchanged at 6,200lbs and don’t necessarily plan on going past that. Also fully understand that air bags do not replace weight distribution as restoring front axle load is critical on any rig.
Gonna get out and tow this afternoon and see how she goes / mess with system pressure some. I think reducing sag from 3” to 2” will be fine / enough for my needs.
Just happy to have piece of mind that the gear is good to go with tons of overhead at Max weight rating. Duramax is not phased and tugs around all /
Combined 18,000 or so pounds without breaking a sweat up and down and around through the Rocky Mountains here in Colorado.