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Wheel size update?

UnsungZero_OldTimeAdMan

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It actually made a pretty big difference for me. I swapped my 22" Sports for 20" AT's and my efficiency took a crap.
We’re not talking about efficiency here. We’re talking about change in overall diameter and effects of that on instrument readings and calculations, deviation from what each vehicle was configured and programmed with when they rolled off final assembly.

Strictly in context of wheel/tire packages… Efficiency is result of rotational mass and rolling resistance.
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windblowlc

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If you are upsizing in the swap I wouldn’t worry about. Calculations and comsumption may be a bit off but on upsizing your odometer will be off which means you accumulate miles slower. Longer warranty that way. 10% larger from the 21’s means another 17,000-18,000 miles or so you can put on before running out of the mileage warranty on the powertrain and battery if you are a high miler type.

now if your downsizing getit updated cause your odometer will read more miles then put on it.
It's not that much of a difference in odometer mileage when downsizing from 275/65R20 to 275/60R20 (which is essentially the same size as 275/55R21). If you take the specs from Tirerack, the difference between the two sizes amounts to 31.3 ft over the course of a mile. So for 50,000 miles it's about 296 miles added to the odometer when you downsize the 20" from the 65 profile to 60 profile.
 

camaroz1985

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They quoted me the same but ended up charging less I think half of that, if I recall correctly.
Last I heard they were claiming you "may" need cameras recalibrated so it had to be done at the SC. Was that not the case for you?

This is why I went with 275/60R20s, don't have to worry about reprogramming. Thinking of getting another set in the same size AS tires when the 21s wear out and just swap back and forth between the two 20s for summer/winter.
 

monzarottie

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OTA? Did the same recently and have a request in. This would be good info to have. Thx roger!
Yes, via
I’ll certainly inquire about that! Please let us know if it actually happens!
OTA for the tire swap was a no go. Mobile Service will make a complimentary house call to update my vehicle configuration.
 
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atebit

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Yes, via


OTA for the tire swap was a no go. Mobile Service will make a complimentary house call to update my vehicle configuration.
Do you have that it writing? Because I’d like to see that in writing to update my upcoming service ticket. :)
 

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monzarottie

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Do you have that it writing? Because I’d like to see that in writing to update my upcoming service ticket. :)
Mobile Service Appointment
Rivian R1T R1S Wheel size update? IMG_2914
 

Arky

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It's not that much of a difference in odometer mileage when downsizing from 275/65R20 to 275/60R20 (which is essentially the same size as 275/55R21). If you take the specs from Tirerack, the difference between the two sizes amounts to 31.3 ft over the course of a mile. So for 50,000 miles it's about 296 miles added to the odometer when you downsize the 20" from the 65 profile to 60 profile.
That tire size difference is 3.3% circumference, which would actually add 1650 miles onto your 50,000. Still not a whole ton, but noticeable, as it's extra "miles" for no reason and it would mess up your range estimates a bit.
 

windblowlc

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That tire size difference is 3.3% circumference, which would actually add 1650 miles onto your 50,000. Still not a whole ton, but noticeable, as it's extra "miles" for no reason and it would mess up your range estimates a bit.
I used Tirerack specs for the Nitto Ridge Grappler for calculations. It said the following -
275/60R20 Diameter 33.2” Revs per mile 625
275/65R20 Diameter 34.1” Revs per mile 605
33.2 x 3.1416 x 625 / 12 = 5432.3’
34.1 x 3.1416 x 605 / 12 = 5401’
Difference per mile = 5432.3 - 5401 = 31.3’
Unless Tirerack specs is wrong, the difference per 50,000 miles is 31.3 x 50000 / 5280 = 296 miles
Of course different tires have different specs so ymmv.
 
 








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