Can the dealer change tire size settings?

I went from the stock 265-70-16 to a 265-75-16 tire. Slightly larger diameter. Can the dealer compensate for the change so the odometer and mileage computer are more accurate?

 

No

 

Besides, that tire change is virtually nothing on the speedo or odo

 

Ok. Thanks.

 

And speedometers are not GPS so they are up to +- 2% on accuracy.

 

I'm going to guess not, but someone who owns a Techstream setup will know.

There is an aftermarket item that will do it though. While it's not cheap, it is yours after you buy it.

But I'd GPS your speedo carefully. You might find the new tires are spot on. I went from a 215 to a 235 and it's perfect up to 50, then is only 2mph off at 60+. Even though it's a 7% taller tire.

 

They are never plus, that would be a huge lawsuit. They are usually -3-5%. There are rare occasions where they have been spot on but that led to legal trouble (Honda)

Running a 265/75-16 tire will make the speedo read more accurate, maybe dead on or slightly low, better check with a GPS

 

Just stating the SAE calibration specs man. I'll tell them they are wrong. BrB.

 

I know, and you are absolutely right, that is the spec. However I was a tech for 15 years and never saw anything over, I’ve checked a lot of speedos. I also have checked every car I ever owned since the invention of consumer GPS the only one that was not within -3-5% was my 2002 Odyssey. It was dead on. And Honda got sued for it (not by me, I didn’t give a crap, just want to know how far I can push it before getting a ticket).

 

There's a setting in your head unit to recalibrate for "new" tires. Might not do too much for you, but may help some.

 

Can you quote the path to that location?

 

Homescreen>apps>setup>navigation>detailed navigation settings>calibration>tire change....its deep in there lol.

 

Dang. At least I'll feel better about upgrading to 265/70/17 when the time comes. Thanks!

 

An accurate way to determine your exact speed is by using a GPS unit that displays ground speed. You may find that your speedometer is off one mile an hour at 40 MPH and even more at 50 or 60 MPH.

Each vehicle is a little different when it comes to the accuracy of the speedometer. I also went from stock tires to 265-75-16 BFG All Terrain tires. I have compared my speed by using a Garmin GPS as well as a roadside radar speed display/speed monitor device. The Garmin and the radar agree on speed so I feel that is pretty accurate.

My speedometer at most speeds is off 1 mile per hour. I am actually going 1 mile per hour faster than what is being displayed on my speedometer. I set my cruise control at 65 MPH on the freeway and the GPS usually displays 66 MPH. Sometimes it will jump up to 67 MPH then return to 66. So I think my actual speed is probably closer but just under 67 MPH when the speedometer shows 65. At 45 MPH on my speedometer the radar sign and GPS both display 46 MPH.

From the Discount Tire website:

UP-SIZING OR DOWN-SIZING
Up-sizing, or installing a taller tire, will lead to a speedometer reading that is slower than your actual speed. This is because a taller tire will have a larger overall circumference, which will cause it to travel more distance per revolution than the original equipment tire. Down-sizing, or installing a shorter tire, will cause the speedometer to read a faster speed than you are actually driving. This is because the smaller tire will have a smaller circumference, causing the tire to travel less distance per rotation than the original equipment tire.

 

See page 253 in the 2018 Navigation and Multimedia System Owners Manual.

https://www.toyota.com/owners/resources/owners-manuals/tacoma/2018

 

That can give you an idea of how far you're off.

Or this one https://www.tacomaworld.com/tirecalc?tires=265-75r16-270-75r16

 

I believe this only affects the Nav system and does not caibrate the seedometer and odometer.
¯\_(ツ)_/¯

 

No. You have to purchase an after market device that allows you to change the settings.

 

why would Honda get sued for being accurate on a speedometer?

 

I think you are right. You’d think with today’s technology they would be talking to each other.