Flat Towing the Cybertruck?

[Aileron]

Will the Cybertruck have capability to flat tow behind an RV?

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[ajdelange]

Probably not. Not without dollies, anyway. I am basing that statement on the caveat that the manuals for the current models say not to tow any of them other than very short distances and short means up onto a trailer, for example.

 

[thejohnllama]

Probably not. Not without dollies, anyway. I am basing that statement on the caveat that the manuals for the current models say not to tow any of them other than very short distances and short means up onto a trailer, for example.

Ya, you can’t roll tow AWD vehicles. Gotta put up on a flat bed

 

[CyberCop]

If this was possible it would increase sales for the RV markets.
can you imagine... as you tow it the regen would charge the vehicle.
wondering if this is a possible 3rd party hack.
of course it might negate your warranty

 

[ldjessee]

If this was possible it would increase sales for the RV markets.
can you imagine... as you tow it the regen would charge the vehicle.
wondering if this is a possible 3rd party hack.
of course it might negate your warranty

Well, if you could connect the CyberTruck so that it only did regen when you wanted to brake (like from a brake controller), that would be useful.

Most manufacturers do not want you to flat tow an AWD due to the extra wear on the drive train the way it is designed in most vehicles.

 

[Mammalian04]

Thank would be a bummer. I've already confirmed with Rivian (early reservation made) and Atlis (vaporware for now) that their trucks will be flat towable. We know that the F-150 is and there shouldn't be any reason the F-150 Hybrid is not. The F-150 full electric is still up in the air. I really want to keep my Cybertruck reservation but not being flat towable would kill the utility for me.
Does anyone know a way to get this answered? I was able to obtain an answer from Rivian pretty easily but the channels I've tried with Tesla have not resulted in any response.

 

[Mammalian04]

Regarding the reason for flat towing not being allowed in traditional ICE vehicles...
It all has to do with the lubrication of the transmission. Most vehicles require the engine to be running to properly lubricate the transmission. With a vehicle in neutral, there are still a number of components spinning and therefore requiring lubrication.

4WD Vehicles with a "transfer case" that have a a neutral position (some 4WD transfer cases like my Excursion don't have this) completely disengage the transmission. In this case, the front wheels are disengaged because you are not in 4WD. The rear wheels are still engaged and you will see the drive shaft spinning but the drive shaft is no longer connected to the transmission components. And lastly, the rear differential will still be spinning but this is not a problem because the differential self lubricates in a "bath" just as it does under regular operation.

Now... With electric vehicles the whole scenario is different. Different manufacturers are using different drive systems such as Tesla Cybertruck with 1 rear motor or front and rear motors (or 2 rear), Rivian R1T with 4 independent motors, Lordstown Endurance with 4 hub motors in wheels. These are just the different motor systems. Then we have to consider if there will be drag and such with that motor design. More technical than I have looked into but the summary is that we just need each manufacturer to tell us yay or nay.

Being an RVer and having pulled vehicles with my motorhome many thousands of miles (Jeep 4WD and F-150 4WD), I just want to keep it simple and allow the vehicle to be pulled by the motorhome. Regen braking adds a WHOLE lot more complexity over the relative simplicity of towing like a traditional vehicle. Here is an explaination of the components of a traditional setup. We'll take my F-150 for example.

WIRING:
1) Motorhome has a normal trailer plug receptical. And Umbilical cord goes back to the flat towed vehicle that sends 12 volt power, Left turn, Right turn, running light, and brake light signals.
2) The F-150 has a diode protected "splice" into its wiring so the signals provided by the motorhome light up the appropriate tail lights. The diodes just keep any signals create by the truck from backfeeding into the motorhome (that would create problems).
3) The F-150 has an aftermarket braking system installed. These are not cheap $1700-$2000 installed.
The system looks for 2 things before activating the brakes in the towed vehicle. The first is of course a brake light signal from the RV that you are pressing the brake.
The second is an accelerator based signal that it checks on its own to make sure that you really are slowing down and its not just a false brake signal. Something like that could burn up your brakes if the brake signal is on somehow and you are happily continuing down the highway. Brakes have caught on fire this way and burned vehicles (and RVs with it) to the ground.
When the braking system is activated, it triggers an vacuum on the towed vehicles braking system. If your vehicle was running, it would create its own vacuum but since it is off, your braking system is spliced into the brakes vacuum lines. It simultaneously has a arm or cable physically attached to the brake pedal in your towed (aka toad) vehicle and pulls or pushes the pedal. The pedal uses the vacuum system to activate the brakes (without the vacuum, you would have to push the pedal REAAAAALLY hard to get the brakes to slow your car down - that's how it was in the old days before hydraulic brakes).
4) Charge wire - The motorhome is providing power to the "toad" vehicle so that it can run the braking system. Some people skip this part but I have had a dead battery on a previous vehicle after a long 12 hour day of driving.

PHYSICAL CONNECTON
1) Tow bar: The tow bar needs to have hard points at the appropriate location on the toad vehicle to attach to and not be at risk of just ripping out of the toad and causing runaway vehicle highway mayham.
2) Base Plates: The mouting points on the toad are called Base Plates: This is easy to add on trucks as the front tow hooks are removed and base plate mounts are added to the front of the frame in place of the tow hooks. On unibody vehicles without a traditional frame, it gets a little trickier as you have to find places to bolt to that aren't weak enough to be ripped out. A third party (e.g. Roadmaster or Blue Ox) usually makes these to connect with a tow bar made by the same base plate manufacturer. If the vehicle can resolve the transmission disconnection requirements, the base plate manufacturers have generally done the R&D to make a base plate for that vehicle.
3) Safety cables: in case the tow bar fails (or some similar component) saftey cables attach to your motorhome and to the baseplate or other strong point on the toad. These are just like safety chains on a trailer and are required.
4) Brake failsafe: This is a thin cable that pulls a failsafe is the vehicle becomes disconnected from the tow bar. Important: the safety cable needs to be shorter than the safety cables so that if a disconnection occurs, the failsafe is pulled and the toad starts activates its brakes and starts to slow down (and doesn't smash into the back of the motorhome too!).

So there you have it.
A) Drivetrain requirements
B) Electrical and Braking Requirements
C) Hard point/tow bar requirements

These things aren't not hard concepts but are a WHOLE lot easier if the "toad" vehicle manufacturer has considered them in their design (Ford does a great job at this). Tesla did not do that on the Model X and I therefore can't tow mine.

I want to advocate that Tesla address the requirements above to make it as easy for them to include these features as possible. Adding regenerative braking just adds more complexity for not much benefit. If they include this as a bonus, great but I wouldn't want them not to accomodate the greater need for fear of the engineering headache of regen braking.

 

[mxdoc55]

How bout simple old school mechanical lock out hubs. Had them on the front of my ‘79 Bronco. Put em on all 4 wheels. Easy peasy. Only have to touch them when hooking up for towing. Forget complexity of regen braking. First order principals. I want to tow my damn Cybertruck.

 

[JBee]

Regarding the reason for flat towing not being allowed in traditional ICE vehicles...
It all has to do with the lubrication of the transmission. Most vehicles require the engine to be running to properly lubricate the transmission. With a vehicle in neutral, there are still a number of components spinning and therefore requiring lubrication.

4WD Vehicles with a "transfer case" that have a a neutral position (some 4WD transfer cases like my Excursion don't have this) completely disengage the transmission. In this case, the front wheels are disengaged because you are not in 4WD. The rear wheels are still engaged and you will see the drive shaft spinning but the drive shaft is no longer connected to the transmission components. And lastly, the rear differential will still be spinning but this is not a problem because the differential self lubricates in a "bath" just as it does under regular operation.

Now... With electric vehicles the whole scenario is different. Different manufacturers are using different drive systems such as Tesla Cybertruck with 1 rear motor or front and rear motors (or 2 rear), Rivian R1T with 4 independent motors, Lordstown Endurance with 4 hub motors in wheels. These are just the different motor systems. Then we have to consider if there will be drag and such with that motor design. More technical than I have looked into but the summary is that we just need each manufacturer to tell us yay or nay.

Being an RVer and having pulled vehicles with my motorhome many thousands of miles (Jeep 4WD and F-150 4WD), I just want to keep it simple and allow the vehicle to be pulled by the motorhome. Regen braking adds a WHOLE lot more complexity over the relative simplicity of towing like a traditional vehicle. Here is an explaination of the components of a traditional setup. We'll take my F-150 for example.

WIRING:
1) Motorhome has a normal trailer plug receptical. And Umbilical cord goes back to the flat towed vehicle that sends 12 volt power, Left turn, Right turn, running light, and brake light signals.
2) The F-150 has a diode protected "splice" into its wiring so the signals provided by the motorhome light up the appropriate tail lights. The diodes just keep any signals create by the truck from backfeeding into the motorhome (that would create problems).
3) The F-150 has an aftermarket braking system installed. These are not cheap $1700-$2000 installed.
The system looks for 2 things before activating the brakes in the towed vehicle. The first is of course a brake light signal from the RV that you are pressing the brake.
The second is an accelerator based signal that it checks on its own to make sure that you really are slowing down and its not just a false brake signal. Something like that could burn up your brakes if the brake signal is on somehow and you are happily continuing down the highway. Brakes have caught on fire this way and burned vehicles (and RVs with it) to the ground.
When the braking system is activated, it triggers an vacuum on the towed vehicles braking system. If your vehicle was running, it would create its own vacuum but since it is off, your braking system is spliced into the brakes vacuum lines. It simultaneously has a arm or cable physically attached to the brake pedal in your towed (aka toad) vehicle and pulls or pushes the pedal. The pedal uses the vacuum system to activate the brakes (without the vacuum, you would have to push the pedal REAAAAALLY hard to get the brakes to slow your car down - that's how it was in the old days before hydraulic brakes).
4) Charge wire - The motorhome is providing power to the "toad" vehicle so that it can run the braking system. Some people skip this part but I have had a dead battery on a previous vehicle after a long 12 hour day of driving.

PHYSICAL CONNECTON
1) Tow bar: The tow bar needs to have hard points at the appropriate location on the toad vehicle to attach to and not be at risk of just ripping out of the toad and causing runaway vehicle highway mayham.
2) Base Plates: The mouting points on the toad are called Base Plates: This is easy to add on trucks as the front tow hooks are removed and base plate mounts are added to the front of the frame in place of the tow hooks. On unibody vehicles without a traditional frame, it gets a little trickier as you have to find places to bolt to that aren't weak enough to be ripped out. A third party (e.g. Roadmaster or Blue Ox) usually makes these to connect with a tow bar made by the same base plate manufacturer. If the vehicle can resolve the transmission disconnection requirements, the base plate manufacturers have generally done the R&D to make a base plate for that vehicle.
3) Safety cables: in case the tow bar fails (or some similar component) saftey cables attach to your motorhome and to the baseplate or other strong point on the toad. These are just like safety chains on a trailer and are required.
4) Brake failsafe: This is a thin cable that pulls a failsafe is the vehicle becomes disconnected from the tow bar. Important: the safety cable needs to be shorter than the safety cables so that if a disconnection occurs, the failsafe is pulled and the toad starts activates its brakes and starts to slow down (and doesn't smash into the back of the motorhome too!).

So there you have it.
A) Drivetrain requirements
B) Electrical and Braking Requirements
C) Hard point/tow bar requirements

These things aren't not hard concepts but are a WHOLE lot easier if the "toad" vehicle manufacturer has considered them in their design (Ford does a great job at this). Tesla did not do that on the Model X and I therefore can't tow mine.

I want to advocate that Tesla address the requirements above to make it as easy for them to include these features as possible. Adding regenerative braking just adds more complexity for not much benefit. If they include this as a bonus, great but I wouldn't want them not to accomodate the greater need for fear of the engineering headache of regen braking.

If done right regen braking won't add any complexity to the Cybertruck. All you would need is the mechanical and electrical connections and a controller that interfaces with the CTs CAN bus. With this you would only need to "start" the CT, put it in drive and then modulate the CT accelerator and braking signals.

The CT aleady automatically switches between regen and friction braking all by itself. You can also command the CT to assist with the acceleration of the motorhome and CT depending on your mechanical connection limits. But at a minimum the CT could act as if it weren't there going uphill, by offsetting its own driving load, and then on the flat it could coast or run with a mild regen to charge the battery so you end up with a full CT at the end of the trip if you need it.

When going downhill you could do the same, but here it would be really nice to regen the motorhome potential energy as well, so effectively reducing motorhome brake wear, and collecting all that additional energy to charge the CT. The same would apply to stopping for lights etc and this regen effect would essentially make the towing motorhome a hybrid.

The question is what type of motors the electric vehicles use, with brushless motors you can't easily coast them without energy regen/consumption like you can with induction motors. But I'm pretty sure the CT will get the Plaid induction motors so it should work.

I'd expect that just by using the downhill and stopping regen alone of the vehicle combo, will add range to the CT without adding fuel consumption to the motorhome. Unless the terrain is super flat and theres no reason to slow down of course. If the CT is used for active regen and acceleration of the motorhome, like a hybrid would, I would expect a motorhome fuel consumption reduction, or a fuller CT battery than when you left on that trip. You could choose between either over the towing app and CAN controller.

Overall I would want CT regen to work whilst being flat towed by a motorhome. On top of the savings mostly because then I can use the motorhome to give the CT a quick charge through the tow, meaning I don't have to find a charger when I'm out yonder. Then I can use the CT battery for boondocking for at least week or two instead of running a noisy generator.

The other integration that would be nice would be a "puppy mode" where the FSD would actively track some fiducial tags on the rear of the motorhome using its cameras. That way the CT could be connected by a single straight tow bar for transferring acceleration and regen loads, but would actively steer itself using its 4WS to follow the track of the motorhomes rear wheels. This would mean the motorhome does need to swing out to get the CT around the corner. There would actually be a way for using this same feature to more easily reverse the CT as well, or at least use the CT cameras for reversing.

Technically puppy mode could work without any connection at all to the motorhome. The CT FSD would be able to accurately measure the distance between the motorhome and CT using its already built in ultrasound and visual sensors and even see the motorhome brake lights just in case too. This would just be a FSD code upgrade that can come in a over the air update and would cost nothing in equipment, but you wouldn't be able to regen without the towbar, and its probably not legal...yet. So you would just have to tell it what numberplate to tailgate.

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