There have been a number of people (thread, thread) wondering about fitting the 18" Aero wheels from Model 3 on Model Y. The motivation for me is installing winter tires on a more efficient wheel that allows a taller sidewall. There are a couple things to consider: Brake caliper clearance I expect the regular Model Y brakes will fit within the barrel section of the Aero wheels but I haven't seen this demonstrated. The question is whether the regular rear calipers are different between the 3 and Y. If they're the same, the 18" Aeros should fit. It looks like the Aero's will NOT fit the Model Y Performance Upgrade brakes per this post (H/T @RoBoRaT). Wheel size The 18" Aeros are 18x8.5 ET40, narrower than the 9.5" wide and ET45 19" and 20" wheels on Model Y. Using something like a 245/50R18 or 245/55R18 tire results in a similar outside tire fit as the regular Model Y. The inside of the tires would have about 10mm more clearance to the suspension. This is all good, especially for winter tires that can benefit from the slightly narrower tread. Wheel load rating The 18" Aero's are marked with a 700 kb (1543 lb) rating (picture, H/T @RoBoRaT). This is where the challenge lies and what led me down the rabbit hole looking at Model Y Load limits. I plotted the Gross Axle Weight Ratings from pg 189 of the Model Y Owners Manual and added an equivalent line for 18" Aero wheels based on the 1543 lb individual wheel limit. I also plotted the 5302 lb Gross Vehicle Weight Rating for Model Y Long Range. As would be expected, the OE 19"-21" wheels allow the full range of possible axle weights given the GVWR limit. That is, the dashed gray, orange and blue lines are outside the brown diagonal GVWR line. The 18" Aero wheel, assuming a 3046 lb GAWR, would not allow very heavy, rear loading of Model Y without overloading the rear wheels. Let's zoom in and look at these different load configurations to see how big of an issue this could be. Config A: Curb weight, no payload Config B: Driver only Config C: Two front passengers Config D: Driver, two kids in back, and some stuff in the frunk and trunk Config E: Two big guys in front and a full frunk Config F: Four adult passengers Config G: Fully laden with four adult passengers and 205 lb cargo Config H: Fully laden with two adult and two smaller passengers and 295 lb cargo Config I: Fully laden with driver and 715 lb cargo Config J: Same as I but with cargo moved forward to stay ahead of 18" Aero rear axle limit Config K: Fully laden with speculated 320 lb tongue weight trailer Config L: Same as K but with only 265 lb tongue weight to stay ahead of 18" Aero rear axle limit Config M: Driver and minor cargo with 320 lb tongue weight trailer Caveats: - The axle loading calculations assumed approximate locations for the respective weights in the table, but they're pretty close. - Nothing has been officially published yet on Model Y tow rating. - This only applied to Model Y LR AWD. The RWD and/or Standard Range cars will have different results. From this, I conclude the 18" Aero can be used on Model Y LR AWD as long as special consideration is paid to keeping the payload forward when close to the GVWR. YMMV and all that.
@Zoomit: Wow, thanks for the detailed information. Is it safe to use the 20" Model 3 Sportwheels on Performance Model Y? Again thanks for the above details!
245/55 18 or 245/50 18? What is the height of these sizes compared to the stock 19. (Edit: other thread says the 50 is smaller and the 55 is larger, .5 inch.) Also, will the software allow selection of an 18". 19, 20 and 21 are the stock sizes. Can I select 19 even though the tire is 18? I have an extra set of aero wheels, so this would be a nice winter option.
I have no idea what the load rating is for either the 19" or 20" Sport wheels. I failed to mention previously that one of the reasons I'd be comfortable using the 18" wheels on Model Y is because the tall sidewall reduces the impact loads to the wheel (yes, it flattens the curve!). The larger wheels have shorter sidewalls which transmit higher road forces, from potholes for example, to the wheels. Then you need to question why the Tesla engineers used 9.5" wide wheels for the Model Y. The Model 3 wheels are only 8.5". 255 tires can fit on 8.5" wheels but yet they went wider. Was it for aero efficiency, steering feel, load rating? I'm not sure. The software wheel selection adjusts the trip efficiency predictions and the graphics. That's it. It'll only have the original equipment options, so don't expect to be able to select the 18" wheels. Just select 19".
I'd want wheels that meet or exceed axle ratings. I wonder what regulations exist for using wheels below axle ratings. On my F150 HDPP they used 7 lug wheels (2,400lb capacity wheels) to preclude the use of other F150 wheels which have lower ratings.
@Zoomit I've been looking for the load rating for 20" Sportwheels but can't find legit info. I have a set of 20" Sportwheels, and no marking for load rating (like the one 700kg in 18" Aeros) seen on one. Don't have a clue and can't decode all the markings that could be the load rating. I'm going to look at the other 3 and see if with load rating marks.
All your wheels should have the same markings. None of them appear to be a load rating to me. I looked at my 19" Sport wheels and found similar types of markings as your 20", though it's a lot harder when the wheel is mounted on the car to be sure.
Not really. The only meaningful difference is the limit on the front axle, but it’s impossible to overload it anyway. I had already updated the charts with the front axle limit and corrected hitch tongue limit for this thread: Model Y Cargo Loading Config A: Curb weight, no payload Config B: Driver only Config C: Two front passengers Config D: Driver, two kids in back, and some stuff in the frunk and trunk Config E: Two big guys in front and a full frunk Config F: Four adult passengers Config G: Fully laden with four adult passengers and 205 lb cargo Config H: Fully laden with two adult and two smaller passengers and 295 lb cargo Config I: Fully laden with driver and 715 lb cargo Config J: Fully laden with 350 lb tongue weight trailer Config K: Driver and minor cargo with 350 lb tongue weight trailer Config L: Two front passengers with 971 lb in trunk
Amazing analysis as always. I really wish the MY came with 18" Aeros from the factory as when initially debuted. The 19s are unnecessary and not as good looking as the Aeros, IMHO. Plus, I already have great snow tires for them! haha
I've read through 3 threads on this topic and I'm still a litlle confused. Has anyone actually put 18" Aeros on a Model Y and confirmed that they fit? Is there an issue with sensors not being compatible? And if so, is the solution as simple as changing to the new sensors?
That is amazing data. I see that Martian Wheels has an 18" for the Y. I would love to know if 18" aeros fit, as I'll be looking for a winter tire solution and I would prefer to go 18" and narrower.
This LR AWD owner put 18" Aero wheels on, so they will clear the brake calipers. His video/picture, not mine. The rear brake calipers on Performance with (red) PuP calipers are bigger/sticks outward more than the regular rear brake calipers, so I have not actually mounted an Aero wheel on the rear. I am to damage the calipers. You will need to buy new Bluetooth TPMS sensors from Tesla Service/Parts at $75 each.
So the TPMS system is different on the Y? ie TPMS sending units for the Model 3 won't work on the Model Y?
That sucks. Hopefully there will be some good 3rd party options for the bluetooth sensors, before winter hits / by the end of the year.
Won’t 18” wheels change your speedometer and odometer readings? Seems like 235/50/18 would be close enough or would this still throw things off a bit? Here’s a comparison between MW03 19x8.5 and a 18x8.5 wheels with 19/18 tires, respectively. I’m contemplating between Martian MW03 19x8.5 and 18x8.5 right now...
Wheel size has nothing to do with the speedometer calibration. That depends completely on tire outer diameter. The stock 19" tires are 255/45R19, not 235. This thread is about using the Model 3 18" Aero wheels, which would optimally have a 255/50R18 tire to match the OE tires, but that size isn't available with any real selection of tires. The closest sizes that do have tire choices are 245/50R18 or 245/55R18.
I suppose it’s worth also showing stock 19” Gemini tire size as compared to the MW03 18x8.5 since there seems to be much more difference which looks like it would throw off speed/mileage. So I may have answered my own question? I was hoping to get: (a) a lighter wheel for weight reduction and efficiency gains (b) a slightly narrow wheel for less rolling resistance (c) not throw off my speed and odometer - the speed is the bigger issue because it would drive me nuts. So maybe the safest bet is to go with MW03 19x9.5 after all is said and done... I just don’t know what to do