Towing with Mid-Size and Full-Size Vans: High Elevation? Will You Test It? [Ask TFLtruck]

towing with commercial vans ram promaster
Ram ProMaster City on the Ike Gauntlet

Did you know that high altitude negatively affects towing capacity on all kinds of vehicles, including vans? Will TFLtruck take vans, such as the Mercedes-Benz Metris on the Ike Gauntlet test? There are two very important questions here, sent in by Greg Richards.

Here is what Greg writes:

I’d like to see an Ike Gauntlet run with the Mercedes-Benz Metris, and see how well that 2.0L Turbo 4-cylinder really works at high elevation. It’s max towing capacity is listed at 5,000 pounds. However, the Mercedes owners manual also states:

Driving in Mountainous Areas:

When driving in mountainous areas, note that the power output of the engine, and with it its gradient climbing capability, decrease with increasing altitude. Please take note of this particularly when driving with a trailer in mountainous areas.

The maximum permissible trailer loads are valid for journeys at altitudes up to 1,100 yds (1,000 m) above sea level with gradients up to 12%.

So, it can’t actually tow 5,000 lbs at elevation. Maybe something like a 3,000 lbs pop up camper or boat would be better for the test?

First of all, yes – we would love to test more vans. This includes hauling weight inside the van, towing a trailer, running highway MPG loops, and more. We have asked for a Mercedes-Benz Metris, Sprinter, and vans from other manufacturers. However, these are difficult to come by for tow testing.

2016 ram promaster ecodiesel towing trailer
Ram ProMaster EcoDiesel

How does high altitude, such as the Ike Gauntlet extreme towing test, affect a truck’s towing capacity? The Ike Gauntlet test maxes out at 11,158 feet above sea level (aka. 3,400 meters above sea level). Several manufacturers, such as Ford and Mercedes-Benz have communicated warnings about high elevation decreasing the towing capacity of their trucks and vans. Indeed, the lower air density at high elevation starves engines for oxygen, thus reducing power. A naturally aspirated engine can lose as much as 30% of its power at an elevation of 11,158 feet. Turbocharging helps fight against this power loss, but no engine can fully counteract the affects of high altitude.

Check out this Mercedes Metris first drive overview.