Need help fixing range while towing (it’s 30% 😵)

[Flyedouglas]

Good morning all! I’ve been in the market for a travel trailer for awhile now. I wanted to experience towing with my R1S and get some idea on the actual towing range I should expect so I rented the exact model I’ve been looking into and towed it to a campsite 180 miles away for a few days. While the truck did a great job towing my range was much less than expected (I’ve been reading up on Rivian towing for months). I’d love to have any thoughts/ideas on things I should consider checking or changing for the trip back to try to increase my range any. I’ll list some details below about the trailer and how I towed it…

Gen 2 R1S Dual Motor Max Pack
-Set to FIRM with Regen HIGH
-Max speed on highway 65mph (used cruise control most of the trip)
-Very gentle with acceleration and tried to utilize regen braking over manual braking as much as possible.
-Trailer brake gain set to 5

Trailer:
-Loaded weight approx 5,200-5,500 lbs
-Tongue weight approx 460 lbs
-Dimensions 25L/8W/11H
-Weight distribution hitch

Initially when I hooked up and started driving the Rivian estimated the trailer weight at 4,500 lbs. but after awhile I checked it again and it updated to 5,500 lbs.

The outside air temp was in the low 60’s. Winds were fairly gusty a good portion of the trip approximately 15-20mph. There was a bit of stop and go traffic and a few back roads but the high majority of the trip was flat highway, averaging around 60mph (no faster than 65mph) with cruise control on.

My normal range charged to 100% is 410. With the trailer plugged in and driving for a bit both the energy screen and my driver’s side display estimated the full charge range at 225 miles. However the nav display was calculating my charge/mileage at arrival much lower (initially 50 miles less, with the delta slowly growing as the drive continued). As it turns out the nav display was much more accurate.

Then end result was an average of 0.93kwh/mi or approximately 125 miles for a 100% charge.

So first of all can anyone tell me why the energy and driver’s display range estimates would differ from the nav estimates?

Second of all does anyone have any ideas on what I can check/change to possibly increase my range? My only idea so far… while stopped at a charging session I noticed that the trailer was not longitudinally level. The front was sitting higher than the back. Could that be affecting my range that much? I plan to adjust the WDH to have it sit closer to level for the drive back. I’ve attached a photo where you can see how far off it is from level.

Sorry for the dissertation but any help would be sincerely appreciated.

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[sam decker]

Good morning all! I’ve been in the market for a travel trailer for awhile now. I wanted to experience towing with my R1S and get some idea on the actual towing range I should expect so I rented the exact model I’ve been looking into and towed it to a campsite 180 miles away for a few days. While the truck did a great job towing my range was much less than expected (I’ve been reading up on Rivian towing for months). I’d love to have any thoughts/ideas on things I should consider checking or changing for the trip back to try to increase my range any. I’ll list some details below about the trailer and how I towed it…

Gen 2 R1S Dual Motor Max Pack
-Set to FIRM with Regen HIGH
-Max speed on highway 65mph (used cruise control most of the trip)
-Very gentle with acceleration and tried to utilize regen braking over manual braking as much as possible.
-Trailer brake gain set to 5

Trailer:
-Loaded weight approx 5,200-5,500 lbs
-Tongue weight approx 460 lbs
-Dimensions 25L/8W/11H
-Weight distribution hitch

Initially when I hooked up and started driving the Rivian estimated the trailer weight at 4,500 lbs. but after awhile I checked it again and it updated to 5,500 lbs.

The outside air temp was in the low 60’s. Winds were fairly gusty a good portion of the trip approximately 15-20mph. There was a bit of stop and go traffic and a few back roads but the high majority of the trip was flat highway, averaging around 60mph (no faster than 65mph) with cruise control on.

My normal range charged to 100% is 410. With the trailer plugged in and driving for a bit both the energy screen and my driver’s side display estimated the full charge range at 225 miles. However the nav display was calculating my charge/mileage at arrival much lower (initially 50 miles less, with the delta slowly growing as the drive continued). As it turns out the nav display was much more accurate.

Then end result was an average of 0.93kwh/mi or approximately 125 miles for a 100% charge.

So first of all can anyone tell me why the energy and driver’s display range estimates would differ from the nav estimates?

Second of all does anyone have any ideas on what I can check/change to possibly increase my range? My only idea so far… while stopped at a charging session I noticed that the trailer was not longitudinally level. The front was sitting higher than the back. Could that be affecting my range that much? I plan to adjust the WDH to have it sit closer to level for the drive back. I’ve attached a photo where you can see how far off it is from level.

Sorry for the dissertation but any help would be sincerely appreciated.

Did you have a head wind?

 

[endress14]

i may have missed it, but was this the average for the round trip, or just to the campsite? is the elevation of the campsite above where you began?

 

[Cursosegundo]

In my experience, it takes a few trips for the navigation computer to figure out what your range is going to be based on your trailer. But it does seem to get more accurate over time. I have a similar size trailer and rarely get much more than .95kWH per mile. Your max battery pack probably has a usable capacity around 150 kwh x .93 kWh/mi should equal 139.5 miles you can go before it is completely dead. Obviously you’re gonna wanna leave some in reserve. Good luck!

 

[350Industrial]

Your efficiency isn't that bad considering the drag your trailer adds. That trailer is like pulling a parachute behind you. FWIW, I average about 0.7 mi/kWh pulling this:

 

[Zoidz]

You need to moderate your expectations regarding the estimates it calculates. It will improve over time, just as you saw how the weight calculation changed, but it will never capture all the dynamic variables of towing. Head/tail/cross winds, road surface conditions, are you following a tractor trailer, small but impactful elevation changes enroute, etc. can't possibly be estimated.

I tow multiple type of trailers - a landscape trailer, a flat bed trailer with various equipment, a boat and box trailers. I have not towed a camper like your picture, but based on my experience with other trailers and my calibrated eye (lol), you've got significant wind resistance - not just the front, but also side drag and the AC unit on the roof. I'm not surprised that you are under 1 kwh/mile. I could be wrong, but I doubt leveling the trailer by dropping the tongue an inch or two will mach any difference. The biggest changes you can make are to drive slower to reduce wind resistance and/or a smaller trailer.

 

[Mathme]

hard to tell based on the info provided, but I'd try slowing down. The OP stated they were pulling at 65MPH and the winds were blowing 15-20MPH. If those winds were anywhere near a headwind, that's extra drag and could be like driving 80-85.

Even with just a bike rack on my truck, with a 20MPH headwind, I know my efficiency will tank by 10-15% while on the freeway.

Elevation gain will also suck the bottom out of the pack pretty quick. In my truck, going up a 6% grade without a trailer will drop my efficiency would about 1 mile/kWh.

 

[Flyedouglas]

Did you have a head wind?

Best I could tell it was mostly crosswinds and possibly even slight tails winds.

 

[Flyedouglas]

i may have missed it, but was this the average for the round trip, or just to the campsite? is the elevation of the campsite above where you began?

This was one-way. The return will be the day after tomorrow (Thursday). But no significant elevation changes and it was a mostly flat drive.

 

[Dark-Fx]

Get a more aerodynamic trailer. It makes a huge difference. With our 18BH imagine I can get about 135 miles with either of my Rivians from 100%, but a big headwind will murder the range. This summer with it on our Sierra, we could get 200 miles doing 65 under normal conditions. But with a bad headwind it dropped down to almost 150 miles.

 

[mkg3]

Definitely the base drag that's killing the range. The below image and the table shows just how much drag force differs baed on the base drag.

There are two fundamental options:
1) find a aerodynamic shape that reduces base drag as much as possible such as Bowlus

2) find a motorized (electric) trailer such as Lightship to offset the load on the R1S

Or both.

 

[Davethadog]

Buy a diesel if you want to tow well long distances. Sorry but the energy density is just not there.

 

[350Industrial]

Buy a diesel if you want to tow well long distances. Sorry but the energy density is just not there.

I second this advice:

 

[Flyedouglas]

Thanks for all the info. To clarify I’m not looking to tow long distances. I’m trying to determine if there is anything else I can do with my Rivian and/or travel trailer to get the most out of my range. So let me be more specific with my 2 questions…

1. Any ideas why the nav range would be different from the range on the driver display and energy screens?

2. Are there any settings or anything that I should consider toying with that could potentially extend my range?

 

[Dark-Fx]

Thanks for all the info. To clarify I’m not looking to tow long distances. I’m trying to determine if there is anything else I can do with my Rivian and/or travel trailer to get the most out of my range. So let me be more specific with my 2 questions…

1. Any ideas why the nav range would be different from the range on the driver display and energy screens?

2. Are there any settings or anything that I should consider toying with that could potentially extend my range?

Rivian's range is very optimistic versus the calculated weight. I complained about it back when they released the original trailer software. I guess I need to complain via official channels.

Ignoring the above, when I am trailering I try to compare the miles driven against what the truck says I have left. If I drive 10 miles and it reduces my range by 15 miles, I will slow down.

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