Odometer trip report

I bought my truck new in October and just recently took it on a 1200 mile road trip. I was interested to discover that my odometer is off by about 4.5%.

Context: 2021 TRD OR DCSB 6MT with factory lift and 275/70r17 Falken Wildpeaks.

I was curious if my odometer was off due to the larger tires. There were several stretches of road where I compared the odometer to the GPS. The truck consistently showed 95.5 miles for every 100 miles on the GPS.

When I applied that conversion to gas mileage, I was pleased to find I was getting 1-2 mpg better than what the truck was calculating.

Other than that, the truck handled great in the mountains. I drove through Idaho up into western Montana. I'm pretty happy with it.

 

yes larger tires will cause this…

 

Tire calculator

This will show % delta between stock size and size you are running.

However, speedos are notorious for registering a bit fast, so some correction may actually occur with taller tires.

Thanks for doing actual research and math before posting. And particularly for not dropping in with some silly miles-per-tank question!

 

Some great info here, thanks for posting.

I’m running larger tires as well and didn’t know about this.

 

Right. I just thought it was interesting see usage numbers behind it. 4.5% seemed higher than I expected.

 

I had a similar, but lesser %, experience w/ larger tires on my 2006 Tundra. Also affects the speedo reading… with larger tires, you will be going a faster MPH than you are reading.

 

As your tires wear down the diameter changes. By the time they are worn out they will be closer to stock size and your odometer and speedometer will be closer to being accurate. Normally tires at the end of their useful life will be about 1 size smaller than when new. You basically went up 2 sizes so they will still be a little bigger than stock when worn out.

 

I've noticed that. I downloaded a speedometer app on my phone. When I set my cruise to 30, I'm going 31. When I set 60, I'm actually going 62. Not a big difference but I keep it in mind if I'm speeding.