Big Rig or HD Pickup to Tow Heavy? Freightliner Luxury Hauler vs GMC HD 3500 vs Ike Gauntlet (Video)

Which big diesel truck can handle this giant trailer better on the mountain?

freightliner summit hauler gmc hd pickup diesel ike gauntlet towing comparison
Freightliner Summit Hauler or HD pickup truck

Is a heavy duty pickup truck enough to pull a big and heavy trailer in the mountains? Surely, if you are towing within your weight rating. However, a bigger truck like this Freightliner M2 Summit Hauler offers a more stable and confident platform for towing. What is the actual difference? This is precisely why we put these two trucks on the world’s toughest towing test – Ike Gauntlet™ to see how each handle a 42-foot long trailer.

We also did a turning radius test on both of these trucks and were surprised by the results.

Big thank to Transwest for making this comparison possible. They provided both trucks and the trailer.

GMC HD Pickup

The HD truck is represented by a 2017 GMC HD 3500 crew cab 4×4 dually chassis cab with a utility bed. This truck is equipped the 6.6-liter Duramax turbo-diesel V8 with 445 hp and 910 lb-ft of torque and a 6-speed Allison 1000-series automatic transmission. It’s a class 3 truck with a gross vehicle weight rating (GVWR) of 14,000 lbs.

This GMC one-ton retailed at around $60,000 when it was new.

Freightliner Summit Hauler

The big rig is a 2020 Freightliner M2 business class crew cab “sport chassis”. It’s not just any M2. It’s full Summit Hauler luxury conversion. This truck has all the luxury features a modern one-ton truck has and more. It’s powered by a 9.0-liter Cummins turbo-diesel I6 that develops 350 hp and 1,150 lb-ft of torque. An extra heavy duty 3200-series 6-speed Allison automatic transmission does the shifting for this truck.

This is a class 5 truck with a GVWR of 19,500 lbs. This Freightliner’s curb weight alone is pushing 14,000 lbs.

This fully-optioned Summit Hauler retails for around $162,000.


We are towing a 42-foot long Cimarron living quarters luxury horse trailer. The loaded weight of this trailer for this comparison is 18,500 lbs. This is typical what many people tow with their 5th-wheel toy hauler/camper or a gooseneck trailer.

Ike Gauntlet

We call it “the world’s toughest towing test”, because the Ike Gauntlet™ is a 8-mile stretch of interstate highway with a maximum 7% grade and a top elevation of 11,153 feet above sea level. We test both the downhill braking/control and uphill power performance on this mountain.

Turning Diameter Test

Which truck can make a tighter turn and be more maneuverable? Is it a GMC HD crew cab chassis cab or a longer wheelbase Summit Hauler? We were a bit surprised by the Freightliner make the turn-around in a circle that was about a foot and a half smaller than the dually could do. It’s a testament to a greater wheel cut angle the Freightliner offers.

Towing Performance

On the way down the Ike Gauntlet™ the GMC’s transmission and exhaust brake did a great job, but we did have to use one brake application to bring the truck to 50 MPH. The Freightliner did even better. It did not require any brake applications on the way down. We starting the downhill near 50 mph, and this is precisely where the truck stayed all the way down all by itself. This has never happened before since 2013 when we started running the Ike Gauntlet™. The truck’s 3200-series transmission and an engine brake did their excellent work.

On the way up the mountain, the GMC HD made the run slower than we expected with a final time of over 10 minutes. The Freightliner was a bit slower still, but both trucks complete the difficult climb without much drama.

The Freightliner also offers great visibility around the front and on the sides of the truck, although it is much taller than any pickup truck on the road.

If you are doing heavy trailers (over 20,000 lbs) often, and if you have to regularly cross mountainous terrain – then a bigger truck this M2 is a smart investment for the extra confidence and safety. However, the M2 is not a very convenient daily driver to run back and forth to work (naturally).

A dually pickup truck will handle a similar trailer as well – as long as you stay within its ratings. The HD can be used a daily commuter in a pinch.

Check out all the heavy duty towing fun in the video below.