Weird speed reading

[BonzoInBitburg]

I just put on bigger all-terrain tires on my 2019 Jeep Renegade. Now I'm seeing something weird, my GPS says I'm going slower than what the speedometer shows on the dash. It's off by about 5 to 7 MPH when I'm driving on the highway. Has anyone else had this happen after changing tires? Not sure if I should fix it or just roll with it.

 

[SgtSprnt.21]

Hey, that's totally normal and super common with bigger tires. Your speedometer is calibrated for the stock size, so when the tires are bigger, each rotation covers more ground. The speed sensor doesn't know this, so it thinks you're moving slower than you actually are. That 5-7 MPH difference at highway speeds sounds about right for a size or two up.

You can get a programmer like an AEV ProCal or similar to recalibrate the speedometer to the new tire size. Or, if you can live with it, just remember to mentally adjust your speed on the highway. I know a few people just roll with it and use their GPS for true speed.