speedometer calibration/gear ratios

[scjeep]

I installed a supercharger on my 2020 JT Rubicon. 4:10 gears with 35" tires. The jeep shifts in/out between 7th and 8th gears at 65/70mph. It acts like it doesn't know what gear to be in. Will I have to change gears, or can someone reprogram shift points. I have recalibrated the speedometer with the Rough Country 90019A . It doesn't ask anything about gear ratio, so I am assuming it gets it off the VIN. Any ideas????

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[red/green hawk]

Plenty of people have 35s on their JTR and don't have any issues. I'd check with who installed the supercharger and see if there's anything they can do. Or if you installed it check with the manufacturer.