# Understanding the Range Penalty of Towing with Rivian R1T: Results from Real-World Test

Rivian R1T’s first real-world towing test recently showed a 62% range loss when it took an open trailer with a Shelby Mustang GT on it for a trip from Detroit to LA. The combined weight of the R1T, Shelby, trailer, occupants and their cargo was 14,260 pounds. This result is slightly lower than what many had expected given that the load was under the maximum limit.

The data collected from this real world test indicates that the electric truck has 44 miles of range left with 37% battery remaining after 118 miles of travel. With a range of 315 miles (505km) on a full charge, this works out to just 118 miles from the 135kWh battery pack, or about 62% range loss.

It's important to note that more data needs to be gathered in order to come up with any accurate conclusion regarding the range penalty imposed by towing. Nonetheless, this initial result is still quite concerning as it means that even with a relatively light load, there is still a significant drop in range.

For instance, one driver who plans on flat towing his 15-1/2 foot teardrop with an R1S Max was expecting a 35% reduction for its 2,100 lb load. However, based on this test result he should now plan for a 50% loss instead. Similarly, another driver who tows his ORV 22BHS 10-15k miles per summer saw a 75% hit when pulling a similar sized camper.

In addition, Rivian has stated that the calculations done were way off which could mean that the actual range penalty may not be as severe as initially thought. It remains unclear how much difference this will make but it does offer some hope for drivers who are looking to switch from ICE vehicles to EVs and use them for towing purposes.

Overall, while the results of this first real-world towing test for Rivian R1T are disappointing, they do provide us with valuable insight into how these electric trucks perform when put under strain. As such, further testing and research needs to be conducted in order to gain better understanding of the range penalty imposed by towing in order to ensure that drivers can make informed decisions when choosing an EV vehicle for their needs.

#### What happened when @gideontherivian took an open trailer with a Shelby Mustang GT on it for a trip from Detroit to LA?

The combined weight of the R1T, Shelby, trailer, occupants and their cargo was 14,260 pounds. After 118 miles of the trip the range loss was 62%, according to the center screen display, the electric truck had 44 miles of range with 37% battery remaining.

#### What is the maximum range of the R1T?

With a range of 315 miles (505km) on a full charge, that works out to just 118 miles from the 135kWh battery pack, or about 62% range loss.

#### Is there any accurate conclusion regarding the range penalty imposed by towing?

More data is needed to come to any remotely accurate conclusion regarding the range penalty imposed by towing. That said, it's at least mildly disappointing to see a 60-plus percent range reduction towing a load well under the maximum limit, even if at least part of the reduction is due to aerodynamics.

#### How much range reduction can be expected when flat towing a car?

Flat towing a car is no where close to consumption pulling a camper…. Probably would have been at least a 75% hit if they were pulling a similar sized camper. Aerodynamics and therefor speed is a larger factor when towing.

#### How much range reduction can be expected when pulling a camper?

Keeping it to 55 mph I can get 9-9.5 mpg, if I go more like 60mph I drop to ~8.5 mpg. If I go 65-70 mph it is more like 7.5 to 8 mpg. When I tow my camper in my LX570 I get ~8.5-9 mpg, when I tow my brothers ~6k lb built out 40+flat trailer I get more like 12-14 mpg.

#### What speed were they travelling at during this test?

They were travelling at 73mph (117km/h).

#### How much range reduction can be expected when travelling at higher speeds?

In our Tesla’s (S and 3) I get about 20-25% increased usage at >70mph. At 80mph it is like 40%. Completely ball park but I Would bet that the Rivian has even more of a speed penalty for Wh/mi due to increased Cd. My guess is ~1/3 of the increased usage could be do speed putting it as closer to 40-50% increase due to towing.

#### What would be the expected range reduction for someone who plans on towing their 15-1/2 foot teardrop (T@B 320 BD)?

I plan to tow my 15-1/2 foot teardrop (T@B 320 BD) with an R1S Max and was ballparking a 35% reduction for the 2,100 lb load. I suppose that I should really plan for a 50% loss, despite a fairly light, relatively aero load. By way of comparison, I drop from about 23 mpg to about 16 at 55 mph towing the T@B with my Telluride, roughly a 30% penalty.If the R1S Max has 400 miles of range (not necessarily the case - it may be less), that would mean about 234 miles, assuming a 10% reserve. If the mileage penalty is 50%, that means only 180 miles, but both figures are assuming a 100% charge. Using the 80/20 SoC parameters, things drop to 166 and 128 miles at 35% and 50% respectively.Stops every 128 miles (likely more frequently in hot/cold weather) would be quite irritating at the least, and could force a rethink of the viability of ...