Towing Heavy

[NiamLeeSin]

Hey everyone — wanted to share a detailed breakdown of my towing setup.

My combination is a 2016 Yukon XL and Keystone Bullet 2730BH (6550 lbs loaded). I am 220 lbs under the Yukon GVWR, and ~20 lbs under the rear axle rating by relocating the spare tire to the trailer and only carrying kids and wife and snacks in the truck. I have the Max tow package, aftermarket (Mishimoto) transmission cooler, tuned TECM (AFM turned off) snap on tow mirrors (Snap and Zap), spring helper bags (and air leveling shocks), and Blue Ox WDH, power stop Z36 brakes, and KYB gas adjust front struts.

It tows just fine, but not confidently in wind or steep grade climbing, not due to sway, only a little pushing over when a semi passes (probably thanks to friction brakes in the WDH). I recently traveled Floyd Hill on i70 between Denver and Idaho Springs, and it wasn't bad, just slow.

The rear axle rating and overall truck payload are the binding constraints.

Yukon (steer + drive axle):
Cat scale weight, loaded with family and snacks, full tank (spare tire relocated to trailer pass through storage):
Steer axle
2,900 lbs (FGAWR 3600 lbs ~700 lbs under)
Drive axle
4,180 lbs (RGAWR 4200 lbs ~20 lbs under )
Yukon total loaded
7,080 lbs
GVWR
7,300 lbs
Buffer to GVWR
220 lbs under

I've seen a few posts/comments here of heavy towing and I'm curious what others are doing, or if you have any tips on more modifications or stuff I can buy

 

[ReaperHWK]

Looks like you got some squat going on even with the WDH. If you tow often and far I’d look into air bags.

Edit: looks like you have air bags already or the factory air shocks?

 

[NiamLeeSin]

Looks like you got some squat going on even with the WDH. If you tow often and far I’d look into air bags.

Edit: looks like you have air bags already or the factory air shocks?

I have factory air shocks and spring helper bags as well. Do you think I need to adjust the WDH? It was set by Holiday World before I put the spring helper bags in.

 

[strutaeng]

If you could adjust your WDH to shift some load to the front axle, I think that would be ideal. Are you near Hillsboro, TX?

What axle ratio does your truck have? 3.42?

 

[NiamLeeSin]

If you could adjust your WDH to shift some load to the front axle, I think that would be ideal. Are you near Hillsboro, TX?

What axle ratio does your truck have? 3.42?

True, I'll try to adjust load to the front.
The axle ratio is 3.08
I'm in Houston, but I had a trailer tire blowout near Hillsboro TX, and then a second blowout 30 minutes later, and limped at 5 mph on the shoulder to the Bucc-ee's there, and spent the night in the parking lot. I bought new tires all the way around at a tire shop in Hillsboro the next morning (the picture is during the stop at the tire shop, you can see the rear axle tires are off). I think the tires were about 4 years old and needed replacing, and I was just far enough from Houston for the tires to start heating up and going out.

 

[Geotrash]

Hey everyone — wanted to share a detailed breakdown of my towing setup.

My combination is a 2016 Yukon XL and Keystone Bullet 2730BH (6550 lbs loaded). I am 220 lbs under the Yukon GVWR, and ~20 lbs under the rear axle rating by relocating the spare tire to the trailer and only carrying kids and wife and snacks in the truck. I have the Max tow package, aftermarket (Mishimoto) transmission cooler, tuned TECM (AFM turned off) snap on tow mirrors (Snap and Zap), spring helper bags (and air leveling shocks), and Blue Ox WDH, power stop Z36 brakes, and KYB gas adjust front struts.

It tows just fine, but not confidently in wind or steep grade climbing, not due to sway, only a little pushing over when a semi passes (probably thanks to friction brakes in the WDH). I recently traveled Floyd Hill on i70 between Denver and Idaho Springs, and it wasn't bad, just slow.

The rear axle rating and overall truck payload are the binding constraints.

Yukon (steer + drive axle):
Cat scale weight, loaded with family and snacks, full tank (spare tire relocated to trailer pass through storage):
Steer axle
2,900 lbs (FGAWR 3600 lbs ~700 lbs under)
Drive axle
4,180 lbs (RGAWR 4200 lbs ~20 lbs under )
Yukon total loaded
7,080 lbs
GVWR
7,300 lbs
Buffer to GVWR
220 lbs under

I've seen a few posts/comments here of heavy towing and I'm curious what others are doing, or if you have any tips on more modifications or stuff I can buy

I towed a 7500 lb camper behind our 2012 Yukon XL for 5 years and it did great once I got the WDH set up right. The 6.2 in mine ended up needing more cooling capability for the engine and transmission, so I did some work to get that sorted (thicker Denso radiator, Derale 13960 transmission cooler, a stronger torque converter, and the cooling fans from the K5L package). You shouldn't need these mods for a 5.3, but you might want to consider a better torque converter for that 6L80 as it's the weak link. My tongue weight was a little under 900 lbs, and I was able to shift about 350 lbs of that forward to the front axle with the WDH.

Which WDH do you have? My take on your setup is that you would be wise to revisit your setup. You should be able to get more of that weight moved forward pretty easily. Here is my CAT scale readout fully loaded for camping, with 2 adults on board, a full gas tank, a full fresh water tank, and empty holding tanks. Same per axle limits as yours but with a 3.42 ratio.