How to adjust speedometer?

Any idea of how to correct speedometer on 2016 Tacoma? Recently took off 16" wheels and put on 18".

 

If overall tire height is the same it's a wash man.

What was the old & new tire size?

Maybe a programmer???

But there's this...

https://www.tacomaworld.com/tirecalc?tires=265-70r16-245-75r17

 

Took off 265 70 16 new tires are 285 65 18. Seems to make 3 mph at 60 mph. Not familiar with a programmer, what is it?

 

A deal you plug into your OBD. Not sure if adjusting/calabrating tire size/speedometer correction is something currently offered. Might do some google searching...

 

Can't change speedo calculations as of yet

 

Right so should be about ~6% off so an indicated 60mph would be about 63.6mph.

 

I am almost positive you will need a current diagnostic tool like what the Toyota Techs are using in order to get to the ECU/PCM.

Not an ODBII scanner tool, but the actual programmer.

These are very expensive, and usually require a monthly subscription.

In the OLD DAYS; I used to measure the tire/ground with chalk and a tape measure and use a thing called "math" .... then I would count the teeth on the speedometer gear and add/subtract necessary to give the right readout and then install a new gear. Wow I am OLD ... the days when my 4x4 had a thing called a carburator and the rollbar was made of steel and saved your life .... not like the plastic ones now.

Anyways, I have used these diagnostic tools on other vehicles, and in the software setup I can change all the wheel sizes specs etc.

You may have to take it to a Toyota dealership and get them to do it.

www.dealershipcloseouts.com/store/#!/Toyota-Techstream-Dealer-Package/p/49989774

 

This product seems to getting a lot of use for calibrating speedos in other Toyota forums: http://www.hypertech-inc.com/products-speedometer-calibrator.aspx

 

They don't have for the 2016 yet