Model X

Tesla Forums are now read only. To continue the conversation with the Tesla community visit

Switching from M3 to MX

Hi all,

I'm upgrading from a 2018 M3 to a 2017 MX this week (We need an actual 3rd row), and suspect some of you have done the same.

I was surprised to read that the MX doesn't support key cards. Is this true that MX can only be driven by key fob or phone app?

I love never bringing keys with me anymore when I leave the house bc I always have phone + wallet.

Aside from the key card, are there any major differences I should expect moving up to the X but going backward a model year?

Lastly, are there any upgrades you'd recommend exploring on a FSD 2017 MX?

Thanks! I've been browsing this forum trying to get caught up, so sorry if I've missed something obvious.


  • i have a 3 and an X
    they are different vehicles
  • I went from the 2017 MX to a 2020 Model Y.

    There are some features that I miss that the MX has. There are some features that I love about my new MY.

    MX features that I miss: 1) Falcon Wing Doors (FWD)...once a few over-the air-updates (OAU) made the FWD operate better, they are a much better rear door. When in the garage, and loading for a trip, you can have the doors open and walk under them with no obstructions, loading stuff in the back seats and in the back cargo area. Shortcoming of MY, with rear doors open, there's no room to *walk around* them to get to the back cargo area.
    2) Self present doors: all doors in the MX either are self-present or controlled by the UI touch screen. MY, you have to get out and close them, re-enter your PIN-to-Drive code.
    3) Large Landscape center UI....sooo much screen to view....
    4) Second UI in front of the steering wheel: boy do I miss this..even though they have expanded the center UI space for navigation in the MY...I still like a screen in my *road view* without looking to the right center.
    5) Air Suspension system; The *location specific* ability to raise the vehicle is very useful.
    6) Cargo room: The MX has got TONS OF STORAGE SPACE..I've driven the old MX across country twice (SF Bay to New York) and never lacked for space. I moved the daughter from Portland to SF bay, pulling a U-Haul and packed the MX to her gills, then 3 months later all that stuff to her new job 90 miles away, no space issues. I've yet to take a trip with the MY due to COVID, but have viewed many youtubes and think the MY will be OK, but not as spacious as the MX.
    7) Free Unlimited Supercharging (FUSC); I put some 45k miles on my MX with 2 x-country trips and 10 round trips from SF Bay to Seattle...boy I loved the pre-paid FUSC.
    8) Ride: The MX is slightly more comfortable.

    Pluses for the MY:

    1) Faster charging...the old MX was throttled back from a maximum input of 96kW to 80kW with a soft ware update...took some time on my frquent the MY will have a max input of 250 kW and much shorter charge times.
    2) Increased range....the old MX even at ODO of 45 k miles saw a max range of 212 miles (lifetime wh/mile of 343), the new MY has 326 miles of range...I've seen little degradation as my lifetime wh/mile is 256. I now can omit 4 charging stops on my round trip to Seattle, saving about 2 hours each way.
    3) Increased efficency in over- the- road driving : with the same size battery pack, I can now go farther down the road due to better battery management systems; heat pump system to aid in cabin heating; and more efficent motors.
    4) Reduced weight: With less gross vehicle weight, I'm betting that there will be less tire wear and less brake wear, increasing the savings on regular maintenance issues. The milestone will be if the tires on the MY last longer than the originals of the MX (42k miles when changed out) .
  • MX is an engineering marvel. The Falcon wing doors especially.

    1. MX is a battery hogger, when compared to M3 you will be surprised the rate at which you burn the battery.

    2. In 2017 MX not all options were default so make sure to look at the upgrades you get vs. the ones you expect. Battery upgrade is highly recommended, hepa air filter is okay if you are in an area where fire in summer is common but otherwise it is a battery hogger. Auto doors for drivers side is a super plus. Imagine Carrying 2 coffee cups to the car, the door opens sensing the proximity, sit down and press the brakes and the door closes (thats an enginneering marvel only on MX).

    3. No keycard on MX except on the latest model. Once you are used to the M3 ways of no need to carry the keys you have to go back to needing a key fob but then the keyfob has a ton of function on it. I feel this is a step down.

    4. FSD is what differentiates tesla, If i am not wrong 2017 was the year of transformation to H2 for the cameras so it might be better than Version 1 but it will still not be as advanced compared to your 2018 M3.

    5. Final advice, MX is an expensive car with expensive maintainance needs. The best years of any car is the first 3 to 4 years. There is cost benefits of buying a used car but with battery degradation and old technology you might realize that the 2018 M3 might be a better option on many fronts. So if you are upgrading for space (for family) then that trumps all other points against MX but if you are doing to get an experience of MX then get the latest version out there.
  • @mbirnie51 - Congrats on your Y. To be clear, a new MX solves many of your negatives:

    1) New MX charges at 250 kW
    2) Increased range X LR has 360 miles range, Y LR has 326 miles of range
    3) MX has a heat pump now, but the Y is still a bit more efficient with a lower weight
    4) Tire wear differences are hard to compare as the tires are different. 42K miles is impressive on your MX!

    Both are great vehicles!
  • Be prepared to spend more on tires.
Sign In or Register to comment.