Recalibrating for new tires, what does it affect?

[AmishMike]

I get that going to larger tires (from 33's to 35's) will change effective gear ratio and throw off the odometer/speedometer etc.. I hear everyone talk about it changing shift points, does the TCM/ECM not learn? Will it not learn shift points based on drive styles?
I don't care about speedometer or mpg accuracy. My truck seems to shift just fine with the bigger tires. Only had 2000 miles on it before tire change and 5,000 total now.
2020 Rubicon, so yes 4:10's.

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[XraytecH]

It's just something you do when you go up or down on tire size. Mostly for getting an accurate speedometer reading. As for the shift points, your guess is as good as mine.

 

[Sorbs]

Get a Tazer Mini https://www.zautomotive.com/product/tazer-jl-mini/

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