advice on tire sizing for going with 18" winter tires?

[macheboston]

New MYLR driver here.
I'm looking at getting snow all weather tires (Cross Climate 2 in particular) and going down from stock 19" (255/45-19) to 18" to cope with potholed New England roads.

How do you decide between (these seem to be the Cross Climate sizes that are most appropriate):

• 245/45R18 100V
• 245/55R18 103V
• 235/60R18 107V
• 235/60R18 107H

I'm thinking of going with Tsportline's TST 18x8.5" wheels. They recommend 245/50R18. So, I guess I'm leaning towards the Cross Climate 2 245/55R18 103V.

This is all mind boggling to me. I've had snow tires on previous cars, but just went with stock wheels and swap tires twice a year.

Choosing wheel sizes and tires sizes is a whole new can of worms. Help, please

 

[240vPlug]

I am not a tire expert by any means. With that said for best performance you always want to be as close to factory diameter as possible.

A LR with the 19" Gemini wheel has a diameter of 28.04" My calculator says 255/50 18 is the closest match to factory diameter when going down to an 18" wheel/tire (see pics).

My calculation says the sizes in green are all "acceptable". If it were me I would want the one above because it matches exactly the factory diameter of the 19".

Also, I would recommend only purchasing wheels and not a wheel tire combo from online vendors. The combo is usually non returnable.

If you purchase and install the tires locally you can easily get things like balance problems and warranty issues resolved. I speak from experience on this.

 

[ATPMSD]

Generally, you should not vary from a car’s tire size specification, which you will find on a sticker attached to the driver’s door frame and in the owner’s manual.

 

[ATPMSD]

BTW, the load and speed ratings, such as 100V, for the tires you are looking at, is important. You should check your stock tires and ensure that both he load rating, the number, and speed ratings, the alphabetic character, for new tires are equal to or greater than stock. If the speed rating is H or Z, check this table to ensure it exceeds what your current tire requires.

https://simpletire.com/learn/tire-buying-guides/tire-speed-rating?utm_source=google&utm_medium=cpc&utm_campaign=G_Search_NB-DSA&utm_content=URL_ALL&utm_term=&utm_creative=532306468034&gclid=Cj0KCQjwqc6aBhC4ARIsAN06NmNMXXLtEIvvKfsdoelM1zhDJNomexh-AcKptl2OnAd1BPsSGju0dDkaAvbvEALw_wcB

 

[macheboston]

I am not a tire expert by any means. With that said for best performance you always want to be as close to factory diameter as possible.

A LR with the 19" Gemini wheel has a diameter of 28.04" My calculator says 255/50 18 is the closest match to factory diameter when going down to an 18" wheel/tire (see pics).

My calculation says the sizes in green are all "acceptable". If it were me I would want the one above because it matches exactly the factory diameter of the 19".

Also, I would recommend only purchasing wheels and not a wheel tire combo from online vendors. The combo is usually non returnable.

If you purchase and install the tires locally you can easily get things like balance problems and warranty issues resolved. I speak from experience on this.

What website are you using for the green table?

 

[ATPMSD]

I don’t know what he used but this should do the job

Tire Size Calculator

The best tire size calculator. Use our tire size calculator to find tire size specs and suggested tire sizes. Then check prices for all available tire sizes.

tiresize.com

 

[jcanoe]

Tesla specifies different load index values for the Model Y depending on wheel/tire size:

19" - 104 (1984 lbs)
20" - 101 (1819 lbs)
21" - 98 (front) - 1653 lbs, 103 (rear) - 1929 lbs

Tesla currently does not offer an 18" wheel option for the Tesla Model Y, no load index value for an 18" tire is provided. A tire load index of 103 (1929 lbs) for an 18" tire should be adequate. A tire with a load index of 100 (1764 lbs) is too low for the rear axle of the Tesla Model Y.

A tire with a speed rating of V (149 MPH) is adequate for the Long Range Model Y (Top Speed 135 MPH).
A tire with a speed rating of H (130 MPH) is not adequate for the Long Range Model Y.

The Performance Model Y (Top Speed 155 MPH) requires a tire with a speed rating of W (168 MPH) or Y (186 MPH).

 

[macheboston]

Thanks @jcanoe.

Does that mean that a load rating of 101V (1819 lbs) meets the requirements regardless of tire/wheel size?

Looking at the Cross Climate 245/55R18 103V, they have a load rating of 1929 lbs. That's more than Tesla's rating on their 20" or 21" wheels/tires, but less than on their 19".

 

[jcanoe]

Thanks @jcanoe.

Does that mean that a load rating of 101V (1819 lbs) meets the requirements regardless of tire/wheel size?

Looking at the Cross Climate 245/55R18 103V, they have a load rating of 1929 lbs. That's more than Tesla's rating on their 20" or 21" wheels/tires, but less than on their 19".

The Tesla Long Range Model Y when equipped with the 20" wheels has a lower gross axle weight rating (rear) and a lower tow rating when fully loaded than when equipped with the 19" wheels. I believe the load index of 101 is for the 20" tires in recognition of the weight rating of the 20" wheel. For other wheel/tire sizes, 19", 21" a tire load index rating of 104/103 is indicated. You might have difficulty getting a tire shop to sell or install tires that don't have the minimum weight rating for a given Model Y wheel size that comes up in their computer.

The CC 245/55R18 with a load index of 103 should be fine. A tire with a load index of 101 might be OK. too. A tire installer will not find the CC 245/55R18 or any 18" tire in their database for the Tesla Model Y, only for the Tesla Model 3. The Tesla Model Y is at least ~500 lbs heavier than the Model 3 and needs a tire with a higher tire load index than what is shown for the Dual Motor Model 3 when fitted with the 18" wheels, Extra Load (XL) tires, load index is 98.

 

[ATPMSD]

This is the Model Y Manual (current year I believe)

Model Y Owner's Manual | Tesla

Understand the various wheel and tire specifications for your vehicle.

www.tesla.com

I suggest going to Discount Tire and entering your car information to see what they recommend.

Discount Tire | Tires and Wheels for Sale | Online & In-Person

www.discounttire.com

 

[DEMitchel]

Velox sells 18X8 winter wheels for $219 thru CostCo. Costco Velox Wheels | Select wheels for 2021 TESLA MODEL Y (long range/winter only) (18 inch)).

 

[Noflash]

I have 255/55-18. Fills the wheel well nicely, and plenty of protection from curbs.

 

[240vPlug]

What website are you using for the green table?

https://www.1010tires.com/Tools/Tire-Size-Calculator

Never purchased anything from them.

 

[BudYSir]

I have 255/55-18. Fills the wheel well nicely, and plenty of protection from curbs.

Any pics. Im thinking this for a winter set too. No rubbing i take it?

 

[Noflash]

Any pics. Im thinking this for a winter set too. No rubbing i take it?

No rubbing.

 

[tander]

I have 255/55-18. Fills the wheel well nicely, and plenty of protection from curbs.

Do you have any rubbing probs? Almost an inch more ground clearance it looks like too. Speedo off by a couple mph?

 

[Noflash]

Do you have any rubbing probs? Almost an inch more ground clearance it looks like too. Speedo off by a couple mph?

No rubbing at all. I tested early on and when my speedo said 70 mph, I was actually going 71.

 

[imperialhippy]

No rubbing at all. I tested early on and when my speedo said 70 mph, I was actually going 71.

What tires did you go with and would you do it again

 

[Noflash]

What tires did you go with and would you do it again

I went with Vredestein Quatrac Pros and was underwhelmed with snow performance. Leaning towards CrossClimate2 for next time.