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My first X towing trip

Discussion in 'Model X' started by Cosmacelf, Jan 28, 2016.

  1. Cosmacelf

    Cosmacelf Active Member

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    So I used my X for its first towing trip last night. This is a 110 mile trip that has a significant 4,500 elevation gain, mostly near the end up a small mountain followed by a 10 mile downhill stretch to the destination on the other side. In my P85 Model S, I would do this trip using about 130 rated miles going at a nice clip.

    Towing about 1,000 pounds on an open air 8'x5' utility trailer hauling a golf cart, it used 200 rated miles. I had range mode on, and drove the speed limit (65 on the freeway portion, 55 on the straight highway, relatively slowly on the mountain grade, just because I was being cautious with the trailer). On the freeway, it was using around 650 watts per mile, while the mountain grade it was using 850 watts per mile. Temperature was around 40 degrees.

    The car handled great, I barely felt I was pulling something, very stable.

    The trip computer didn't stand a chance. It estimated 33% range remaining at the end (starting with almost a full charge) and I got there with 19% remaining. The range estimate just slowly and steadily declined as the trip wore on.

    And while the car disengages auto steer while towing, it still allows you to use TACC which is nice.

    The one question I had is whether the car cooling system could handle the increased load, and I got no complaints from the car. I'll be doing the reverse trip in much hotter weather in 8 weeks, so we'll see what happens then.

    All in all, I'm very happy with the car's towing capabilities.
     
  2. gavine

    gavine Petrol Head turned EV Enthusiast

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    Very nice...how does the car know you're towing so it can disable auto-steer?
     
  3. efusco

    efusco Moderator - Model S & X forums

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    Thanks for that report. It's a much more realistic scenario for my anticipated towing needs rather than the 5000lb boat report previously posted. All in all I think that's not too bad, but definitely will require a bit of planning. Let us know how the return trip goes (if you're bringing the golf cart back where you started).
     
  4. ohmman

    ohmman Maximum Plaid Member

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    Thanks for the report. So about 150% energy usage compared to your unloaded P85, but you were likely going more slowly while towing. I'm guessing the open air trailer and golf cart weren't very aerodynamic, so that's one part of the equation as well. The thing I'm most interested in is whether something like the Alto Safari Condo, at a little under 2k lbs, will be able to make it between Superchargers. For hauls on a utility trailer, I'm rarely going long-distance - your example is pretty much the maximum I can imagine myself needing.
     
  5. CTemp222

    CTemp222 Member

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    I'm pretty sure when you tow something you put the the car into "Tow Mode"
     
  6. vangogh

    vangogh Member

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    Great information...Thanks
     
  7. flyhigh123

    flyhigh123 Member

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    plus when you plug into the 7 plug outlet, it will detect it and know its in tow mode i assume.
     
  8. Roamer

    Roamer Member

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    A note from the manual.

    Note: In situations where Model X detects aheavy load, it assumes that a trailer is connected and automatically engages TrailerMode. A message displays on the instrument panel informing you that Trailer Mode has been engaged.
     
  9. CTemp222

    CTemp222 Member

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    Yea that's what it's called.
     
  10. Cosmacelf

    Cosmacelf Active Member

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    Almost all trailers should have a connector for brakes lights and running lights, and no doubt the car detects that something is plugged into that connector at the back. My car auto detected trailer mode by itself, and I assume that's how it did it.

    Yeah, I would assume my golf cart trailer load was very unaerodynamic.
     
  11. Bangor Bob

    Bangor Bob Member

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    The mesh load ramps on those utility trailers are giant airbrakes when they're in the upright position. I modified mine to have the ramp slide and lock underneath the trailer, and that helped the gas consumption when pulling it with my old car immensely.
     
  12. dsm363

    dsm363 Roadster + Sig Model S

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    Would a setting where it asks you to estimate the weight of your trailer in Tow mode help? It might give more accurate estimate then.
     
  13. ohmman

    ohmman Maximum Plaid Member

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    I think that's a good idea, especially initially. However, this is a solved problem from a development standpoint and a pretty simple predictive algorithm should be able to make an even better prediction in short time, including aerodynamic effects, etc. A sort of "here's what I should be using, here's what I am using, therefore.." sort of thing.
     
  14. CHG-ON

    CHG-ON Still in love after all these miles

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    Your consumption was better than I expected.
     

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