Flat Tow

[palmer_md]

I've seen several threads about a request to flat tow both the Model S and the Model X, all of which come back from Tesla as not recommended. I'd like to see the Model 3 designed with the ability to be flat towed behind an RV.

There are lots of reasons that flat tow is better than a dolly (not possible with RWD Model 3) or a trailer. There are several possible solutions to make this happen, all of which require involvement from Tesla. That is why I'd like to see a factory option for this feature. Cost would depend on which solution that they choose. Based on the number of times this came up with Model S and X I think there are quite a few people who would choose this option. I expect more with the smaller/lighter vehicle being towed. With just six weeks to pencils down, it may be too late at this point unless they already had it in the works.

Elon suggested in the 2016 shareholder meeting to have a discussion here regarding feature requests, so this thread is to gather some input from everyone who would like this feature added to Model 3 either in version 1 (which might be too late) or version 2.

 

[strykeroz]

I hadn't considered that an issue until now. Thanks for pointing it out.

 

[Saghost]

The only way to do this safely is to put a clutch of some kind into the transmission, something Tesla hasn't done to date which adds both complexity/weight/cost and failure points.

I doubt you'll see it happen, though a dog clutch wouldn't have to be terribly large/heavy - and correctly implemented it could serve as a parking brake as well (three positions - axles locked to case wall, motor locked to axle, axle free to rotate.) Done this way, it might eliminate the weight/cost of the independent parking brake calipers/pads currently on the S and X, which might be enough savings to make it appeal to Tesla.

 

[omgwtfbyobbq]

Tesla could also provide instructions and a disconnect "kit", which on most vehicles with CVs is just the outer CV joint for each driven wheel. It'd be a little more work with the dual motor car, but for flat towing I'd much prefer any option to no option.

 

[UncleMoose]

I actually wrote a longish email to Tesla about 6 months ago outlining what could be done to make it easy to tow a Model 3 behind a motorhome. I've since gone past that to where the Model 3 should just have a "baby elephant" mode - The Model 3 is just instructed to drive 1 car length behind the RV, mimicking all the turn signals, etc. You'd still probably be required to have safety chains, and monitor the range left on the Model 3, but I would think that the actual following would be trivial. Even the range issue would be helped if you could run a charging line from the RV's generator, as long as the Model 3 allowed charging while driving...
Another advantage of this is that a much smaller RV with a low tow rating could still tow a Tesla.

 

[deonb]

The only way to do this safely is to put a clutch of some kind into the transmission, something Tesla hasn't done to date which adds both complexity/weight/cost and failure points.

How does "Low Regen" mode work?

Assuming there isn't something mechanical, it's going to be driving the motors at the same speed as "Normal Regen", right? So what does it do with the excess energy in that case?


But if it is something mechanical, then the same concept can be used to provide a "No regen" mode, which would make it flat towable.

 

[gregincal]

How does "Low Regen" mode work?

Assuming there isn't something mechanical, it's going to be driving the motors at the same speed as "Normal Regen", right? So what does it do with the excess energy in that case?


But if it is something mechanical, then the same concept can be used to provide a "No regen" mode, which would make it flat towable.

Regen isn't the issue, there is a "no regen" mode, it's called Neutral. However, even in neutral the electric motor is spinning and that is a potential issue for the motor (whether it's a real problem or just something Tesla wants to avoid, I'm not sure). It doesn't "do" anything with the energy, the motor just spins freely.

 

[JeffK]

spinning freely and generating heat, active cooling would be off.

 

[Tiberius]

At this point, it'll be possible or not. They won't be changing anything major this late in the game.

 

[palmer_md]

At this point, it'll be possible or not. They won't be changing anything major this late in the game.

I realize that, I just know that it can be done and that Tesla has the know-how to make it happen. Even if it is too late for this feature to appear in version 1 of Model 3, its not too late to have folks speak up to request this feature. If there is enough interest in this they may start working on a solution to be introduced in version 2 or 3 of Model 3.

I'm also not really interested in discussing all the various possible methods that can be taken to accomplish this task. If we want to discuss the various methods in another thread that would be great. This thread is more for a show of interest in Tesla working on a solution for this option.

I just know that we do a lot of traveling already and have to drag around an ICE vehicle since there are not any EV's that have the ability to be flat towed. In the future I'll be retiring and we will undoubtedly be doing even more travel, and it would be nice to have an EV along for the trip. Charging at the RV park is quite easy, it almost a perfect marriage hauling an EV behind an RV.

 

[Tiberius]

I realize that, I just know that it can be done and that Tesla has the know-how to make it happen. Even if it is too late for this feature to appear in version 1 of Model 3, its not too late to have folks speak up to request this feature. If there is enough interest in this they may start working on a solution to be introduced in version 2 or 3 of Model 3.

I'm also not really interested in discussing all the various possible methods that can be taken to accomplish this task. If we want to discuss the various methods in another thread that would be great. This thread is more for a show of interest in Tesla working on a solution for this option.

I just know that we do a lot of traveling already and have to drag around an ICE vehicle since there are not any EV's that have the ability to be flat towed. In the future I'll be retiring and we will undoubtedly be doing even more travel, and it would be nice to have an EV along for the trip. Charging at the RV park is quite easy, it almost a perfect marriage hauling an EV behind an RV.

If the goal is to suggest this to Tesla, I would start a thread on the official forum, if there isn't one already.

 

[JeffK]

I don't want this features at all if it would involve a more complicated, less efficient, gearbox to provide an actual neutral gear. The car is made for driving not for being towed. There's not a real neutral on an EV.

This is not really a problem that's easily solved on an EV especially with the Tesla using liquid cooling.

For RV towing I'd recommend a flatbed or an enclosed trailer of some sort. Heck I've seen an RV that had a car stored inside it (the dude was loaded $$$).

Here's a video of a similar one:
The Mark of a True Luxury RV

 

[Saghost]

I actually wrote a longish email to Tesla about 6 months ago outlining what could be done to make it easy to tow a Model 3 behind a motorhome. I've since gone past that to where the Model 3 should just have a "baby elephant" mode - The Model 3 is just instructed to drive 1 car length behind the RV, mimicking all the turn signals, etc. You'd still probably be required to have safety chains, and monitor the range left on the Model 3, but I would think that the actual following would be trivial. Even the range issue would be helped if you could run a charging line from the RV's generator, as long as the Model 3 allowed charging while driving...
Another advantage of this is that a much smaller RV with a low tow rating could still tow a Tesla.

Hmm. This is interesting new ground. I was focussed on the question as asked - making the 3 towable as a conventional trailer.

Baby elephant mode has a lot of potential, though - having the car on addresses all of the concerns with coming cooling systems or having the motor spinning, and requires little or no new hardware, merely a firmware update.

Ideally, it'd be paired with a bumper mounted hitch that feeds hitch loads back to the Tesla.

This would allow the car to be towed without losing significant range overall, while still allowing it to steer to minimize side load/tire wear on turns and to assist with both acceleration and braking to minimize the load on the tow vehicle.

 

[garsh]

Heck I've seen an RV that had a car stored inside it

My dad had one of these - the back area was big enough to store things like dirt bikes and quads. He ended up buying a Smart Fortwo and it would just barely fit inside.

He ended up getting rid of that setup and now flat-tows a Honda CRV.

 

[deonb]

If the goal is to suggest this to Tesla, I would start a thread on the official forum, if there isn't one already.

Based on Tesla removing the hidden reservation numbers from their website within 72 hours after it came up for discussion on here, I'd say this forum is just fine to get Tesla's attention.

 

[Tiberius]

Based on Tesla removing the hidden reservation numbers from their website within 72 hours after it came up for discussion on here, I'd say this forum is just fine to get Tesla's attention.

It was just a suggestion, don't be a sensitive suzie. Also, just because marketing or whoever is watching doesn't mean the engineering/design team is.

 

[palmer_md]

Elon specifically mentioned posting feature requests on this site during the annual shareholder meeting.

 

[gregincal]

This is not really a problem that's easily solved on an EV especially with the Tesla using liquid cooling.

It seems to me all you need is a tow mode where cooling is active. The power drain should still be fairly minimal.

 

[JeffK]

It seems to me all you need is a tow mode where cooling is active. The power drain should still be fairly minimal.

Well, technically you're generating power by spinning the motor, if there was a super low tow regen mode you could generate the power as you travel but not have enough regen where you use far more gas in the vehicle pulling the car. It'd be plenty of power to keep the cooling system active.

 

[Frank99]

Well, technically you're generating power by spinning the motor

Well, with an AC Induction motor, with no permanent magnets, you're not going to generate any power spinning the motor. Unless Tesla enables regen mode...