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Car and Driver tested several EVs and one of the interesting tests was the towing range.

They compared the Rivian R1T the Hummer EV and the Ford Lighting Platinum.

They each pulled the same 29 foot 6,100 pound camper trailer.

Lightning traveled: 100 Miles

R1T traveled: 110 Miles

Hummer traveled: 140 Miles
 

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Car and Driver tested several EVs and one of the interesting tests was the towing range.

They compared the Rivian R1T the Hummer EV and the Ford Lighting Platinum.

They each pulled the same 29 foot 6,100 pound camper trailer.

Lightning traveled: 100 Miles

R1T traveled: 110 Miles

Hummer traveled: 140 Miles
Hard to beat the Hummer's substantially larger battery.
 

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A lot of people don't understand this. Towing distance in EV's will come down to the largest battery. The aerodynamics of the vehicle really don't matter much if you're towing a brick.
partially true, but a more efficient tow vehicle with a large battery will be the winner, Silverado EV likely an extra 25-40 miles towing over the Hummer. It's not just aerodynamic drag that hurts the Hummer, also larger frontal area than the SilveradoE, Less efficient 3 motor system, and tires that have more rolling resistance.
 

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A lot of people don't understand this. Towing distance in EV's will come down to the largest battery. The aerodynamics of the vehicle really don't matter much if you're towing a brick.
Yes, C&D argued that the aerodynamics of the trailer mattered less to the Hummer since it's already the least aerodynamic. The Hummer also weighed in at 9,640 lbs, so if they can keep some weight off the Silverado, that should help too.
 

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Yes, C&D argued that the aerodynamics of the trailer mattered less to the Hummer since it's already the least aerodynamic. The Hummer also weighed in at 9,640 lbs, so if they can keep some weight off the Silverado, that should help too.
Weight matters little on efficiency over a long drive, drag is a far bigger factor on the Hummer and trailer.

Weight effects energy required to accelerate a vehicle, but is also paid back when slowing the same vehicle in re-gen recapture.

Aerodynamic Drag, and rolling resistance are part of the vehicle base load, and those negative forces are always there, when accelerating, decelerating, up hill, down hill, flat ground the drag base load is always consuming your energy.
 

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I’ve been curious how both normal range and towing would improve with something like a Michelin Defender highway a/t tire considering the Rivian’s range improvement moving from off-road to on-road focused tires. Thinking of just buying the tech bronze accessory rims and making them my “range” tire then keeping the stock rims and tires for off-road trips.
 

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Weight matters little on efficiency over a long drive, drag is a far bigger factor on the Hummer and trailer.
At a constant speed. Weight still matters every time you accelerate (or decelerate).

The Out of Spec guys tested an R1T with a full payload in the bed largely at constant speed and found an about 7% reduction in range, so it's certainly not nothing, but still less of a hit than aerodynamic/other drag. Of course, there are plenty of holes to poke in their test results including that their control should have been with an empty water tote rather than an empty bed given the aero drag of the tote.
 

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At a constant speed. Weight still matters every time you accelerate (or decelerate).

The Out of Spec guys tested an R1T with a full payload in the bed largely at constant speed and found an about 7% reduction in range, so it's certainly not nothing, but still less of a hit than aerodynamic/other drag. Of course, there are plenty of holes to poke in their test results including that their control should have been with an empty water tote rather than an empty bed given the aero drag of the tote.
Ya, 7% reduction at max payload makes sense, what is the correction factor of the test? Environmental factors etc? Likely at least 2%. This is a non scientific test, and done in the open environment, so the real result could be 5% to 10%, right?

With trailers we are talking well over 50% range reductions... I am saying the weight matters "LITTLE" Not ZERO...
 

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I’ve been curious how both normal range and towing would improve with something like a Michelin Defender highway a/t tire considering the Rivian’s range improvement moving from off-road to on-road focused tires. Thinking of just buying the tech bronze accessory rims and making them my “range” tire then keeping the stock rims and tires for off-road trips.
I'm considering doing this too, great minds think alike!
 

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I'd still like to know if the Silverado is going to be able to pull a 5th wheel. Seems like with them sitting a lot closer to the body of the truck, they should be able to get better range since you're not disrupting the airflow twice. I'm guessing it won't be though, because of the sail panels.
 

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I'd still like to know if the Silverado is going to be able to pull a 5th wheel. Seems like with them sitting a lot closer to the body of the truck, they should be able to get better range since you're not disrupting the airflow twice. I'm guessing it won't be though, because of the sail panels.
No, Silverado E will not pull 5th wheels in the initial form, HD versions coming later might, but that is way down the road.
 

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C&D (probably unintentionally) handicapped the Hummer EV and advantaged the Rivian through how they set up the truck beds. Real-world truck/trailer towing range is a complex blend of a bunch of factors. C&D's photos showed the Hummer had two massive spare tires vertically mounted in its open bed. That really messes with the Hummer's already weak aero design and significantly reduced its optimal towing range. On the other hand, the Rivian, already with an aero, frontal area and weight advantage, had a smooth tonneau cover sealing off the bed, further improving its aero. F-150 had a clean open bed. I'd call the F-150 open/empty bed configuration the "proper" configuration they all should have had. C&D could have thrown the Hummer's spare tires into the trailer and opened the Rivian's bed cover and made it more of a "fair fight".
 

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C&D (probably unintentionally) handicapped the Hummer EV and advantaged the Rivian through how they set up the truck beds. Real-world truck/trailer towing range is a complex blend of a bunch of factors. C&D's photos showed the Hummer had two massive spare tires vertically mounted in its open bed. That really messes with the Hummer's already weak aero design and significantly reduced its optimal towing range. On the other hand, the Rivian, already with an aero, frontal area and weight advantage, had a smooth tonneau cover sealing off the bed, further improving its aero. F-150 had a clean open bed. I'd call the F-150 open/empty bed configuration the "proper" configuration they all should have had. C&D could have thrown the Hummer's spare tires into the trailer and opened the Rivian's bed cover and made it more of a "fair fight".
You can't get a Rivian without the power tonneau, so it should be used to give an advantage if there is one. I disagree with you about the spare tires in the Hummer bed, it might have actually improved aerodynamics vs having an open bed.
 

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Ya, 7% reduction at max payload makes sense, what is the correction factor of the test? Environmental factors etc? Likely at least 2%. This is a non scientific test, and done in the open environment, so the real result could be 5% to 10%, right?

With trailers we are talking well over 50% range reductions... I am saying the weight matters "LITTLE" Not ZERO...
When towing something like this large camper trailer, going from the off-road tire (rolling resistance Cr = 0.013) to a highway tire (Cr = 0.010) on the Hummer would only improve your towing range about 10 miles. The biggest issue is the huge 60-70 sq. ft net frontal area, plus the combined aero drag coefficient any towing truck/trailer assembly presents to the air. Also, the heavier the trailer, the more its tires' rolling resistance become a significant factor and the less the truck's tires'. On the other hand, when NOT towing, going to highway tires could kick your range up 10% to over 350 miles EPA equivalent. And you'd get that improvement every day, towing or not.
 

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C&D (probably unintentionally) handicapped the Hummer EV and advantaged the Rivian through how they set up the truck beds. Real-world truck/trailer towing range is a complex blend of a bunch of factors. C&D's photos showed the Hummer had two massive spare tires vertically mounted in its open bed. That really messes with the Hummer's already weak aero design and significantly reduced its optimal towing range. On the other hand, the Rivian, already with an aero, frontal area and weight advantage, had a smooth tonneau cover sealing off the bed, further improving its aero. F-150 had a clean open bed. I'd call the F-150 open/empty bed configuration the "proper" configuration they all should have had. C&D could have thrown the Hummer's spare tires into the trailer and opened the Rivian's bed cover and made it more of a "fair fight".
Towing a trailer the bed on the Hummer is going to be a low pressure area, the tires cause some turbulence, and extra weight, but not really noticeable drag added.
 

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C&D (probably unintentionally) handicapped the Hummer EV and advantaged the Rivian through how they set up the truck beds. Real-world truck/trailer towing range is a complex blend of a bunch of factors. C&D's photos showed the Hummer had two massive spare tires vertically mounted in its open bed. That really messes with the Hummer's already weak aero design and significantly reduced its optimal towing range. On the other hand, the Rivian, already with an aero, frontal area and weight advantage, had a smooth tonneau cover sealing off the bed, further improving its aero. F-150 had a clean open bed. I'd call the F-150 open/empty bed configuration the "proper" configuration they all should have had. C&D could have thrown the Hummer's spare tires into the trailer and opened the Rivian's bed cover and made it more of a "fair fight".
This article is old, but has some interesting, and unexpected results.

 

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This article is old, but has some interesting, and unexpected results.

It’s due to the interaction of laminar and turbulent air flow. A tonneau cover introduces another surface for friction to act against, when there’s free space for air to flow over otherwise. And the tailgate does the same for air flowing under the truck.
 
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