The Ultimate Off-Road Towing Setup: Why I Chose the 2025 GMC Denali Ultimate 3500HD
"What truck should I buy to tow my camper?" It is the question I get asked most often.
While there are plenty of capable trucks on the market, if you are looking to take your camper off the beaten path—down state forest access roads, through gravel, mud, and potholes—you need a specific kind of setup. You need power, but you also need maneuverability.
In this post, I’m breaking down my personal rig: the 2025 GMC Denali Ultimate 3500HD. I’ll explain why I chose the single rear wheel configuration, the modifications I made for off-roading, and the one suspension upgrade that changed everything.
The Platform: 2025 GMC Denali Ultimate 3500HD
When building an off-road towing rig, size matters. Many people assume a dually (Dual Rear Wheel) is the only way to go for heavy towing, but for my lifestyle, that wasn't an option.
Why Single Rear Wheel (SRW)?
I chose the Single Rear Wheel (SRW) with the standard bed rather than the 8-foot long bed or the dually.
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Maneuverability: I do a lot of off-road camping. Trying to squeeze a dually or a long bed through tight forest trails is a nightmare.
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Capability: Even in the SRW configuration, the Duramax Diesel paired with the Allison Transmission offers incredible power without the massive footprint.
The Build: Wheels, Tires, and Stance
I didn't want to keep the truck stock, but I also needed it to be practical. Here is the setup I’m running:
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Leveling Kit: Installed on the front end to get rid of the factory rake.
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Tires: 35-inch BFGoodrich tires.
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Wheels: 20-inch Hostile wheels.
Pro-Tip on Wheel Offset: I kept the wheel offset minimal—very close to the factory specs. Why? When you are off-roading, a wide offset (wheels sticking far out) will sling mud and rocks all over the side of your truck and camper. Unless you want to install massive, goofy-looking mud flaps, keep your wheels tucked in.
The Problem: The "Squat" Factor
Here is the issue with leveling kits on towing trucks: Squat.
When you add a leveling kit, the front end sits higher. As soon as I hook up my bumper-pull camper (which has a hitch weight of roughly 900 lbs), the rear of the truck sags. This points your headlights at the sky and reduces your front-tire traction and steering stability.
To fix this, I installed the Logic IQ Air Suspension System.
The Solution: Logic IQ Air Suspension
This isn't just a standard airbag helper kit. The Logic IQ system actually required removing the factory helper springs. It replaces them with a dual-shock air suspension system mounted directly to the frame and leaf springs.
Why I Love It:
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On-Board Air: It comes with a built-in compressor mounted to the frame and a remote control. No more hunting for a gas station air pump.
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Instant Leveling: In my test, I hooked up the camper and saw significant squat. I used the remote to put 42 lbs of pressure in the bags, and the truck leveled out instantly.
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Ride Quality: This is the biggest factor. Towing down gravel roads and hitting potholes felt smooth. On the highway doing 75 MPH, the sway was non-existent.
The Debate: Is a 3500HD "Overkill"?
My camper is roughly 8,500 to 9,000 lbs fully loaded. This truck is rated to tow nearly 20,000 lbs conventional.
Is it overkill? Yes. Do I care? No.
1500 vs. 2500/3500
You can tow a 6,000+ lb camper with a 1500 (half-ton) truck. However, you will feel every gust of wind and every semi-truck that passes you.
When you step up to a 2500 or 3500:
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Stability: You feel like you have "more truck" under you. You don't get pushed around.
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Comfort: Contrary to popular belief, modern 3500s ride very comfortably. They aren't the bone-shaking rides of the past.
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Safety: You have better braking and control, especially at highway speeds.
Final Verdict
If you are towing anything north of 7,000 lbs, I highly recommend moving up to a heavy-duty diesel platform. And if you do, add air suspension.
Whether you choose Logic IQ (which offers incredible tech) or Airlift (which offers a slightly longer warranty), having the ability to level your load makes for a safer, smoother, and more enjoyable towing experience.
Specs at a Glance:
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Truck: 2025 GMC Denali Ultimate 3500 SRW
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GVWR: 12,100 lbs
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Payload: ~3,600 lbs
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Suspension: Logic IQ Air Suspension (running ~42 PSI towing)
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Tires: 35" BFGoodrich
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