Can the dealer change tire size settings?

I did some internet searching before spending the $250 for the Hypertech calibration module. It was driving me up the wall, even if it was only a few percent off

 

Awesome info. Thanks for the response!

 

That's only for the navigation. Doesn't affect the speedometer at all.

 

best thing I found so far was hypertech which does an inline correction. The computer still see the off nummber but at least your speedo is correct. I compare it to gps for correct speed to ensure.

 

That was me after awhile I caved. worked great for tire change. It has been off with gear and tire change. Need to figure that out.

 

Just have to pull it out again, the app used to calibrate the sender has a section for gear changes too

 

Oh I know that. I mean I input the gear changes and tire changes into the settings and it was not correct (actually off 10mph). When I did only the tire change it was spot on.. I need to map it out and see whats the issue.

Also I guess tip so you don't have to pull it out is leave the USB attached and have the end coiled or available under the dash. That is what I did so I do not have to remove the dash to make any updates. I knew I was going to regear at some point and still have plans for larger tires next round.

 

Why would the navigation be concerned with tires at all if it uses GPS?

 

Just a quick FYI for anyone considering larger tires... I am getting 255/80/17 Copper ST Maxx installed this weekend. I am currently running 275/70/17 BFG KO2s and will be keeping them for resale. They have approximately 30k miles on them but have a lot of tread left. They still look pretty much new but I just want to try out the pizza cutters. Anyone interested let me know. Looking to get around $300 for all four tires.

 

It's off enough to make me what to correct it. I thought Toyota's have incredible accurate speedo due to their fancy Speed Sensors.

 

Not sure the science behind it, but it did NOT work for me, @mesojdm nor @SearArtist

 

Yep. The head unit trick does not work.

Bought a hyper tech because I believe in having an accurate speedo, odo, and mpg.

 

You only use it once to fix and then unplug it right? Would you be willing to sell it? I'm surprised no one on the forums have started a "rental" service like they have for the ECGS tool.

 

Also, some said it takes some driving after doing the head unit "calibration" for it to correct. I did it 3 months ago when I got my tires put on and I just went out for a quick drive to test it for you and can confirm that when the speedometer on my truck reads 60, the GPS says I'm actually doing 63. That's with 32.2" tires.

 

No it stays plugged in behind the gauge cluster.

 

Nice Hijack

 

Sorry... I’ll move along now...

 

Old thread but, that hypertech tool could be used for odometer fraud. Also, just putting a 1" larger tire on your truck is off 2mph @ 60mph, so a truck that's been running that oversized tire for 100K miles would read about 3,300 miles under actual mileage on the odometer....not a huge concern, but think about the guys going up 3"+ diameter.

 

if you leave the USB plugged in you can run the other end under the dash if you ever need to adjust it again. I have mine setup that way and have used it a few times to adjust with tires, gearing etc. Quick change instead of pulling the dash apart each time.

 

Every Japanese brand motorcycle and pickup truck I have owned read around 4 to 6% lower than actual MPH. The tire change might get you right on the spot. Back in the day before GPS you placed the vehicle on cruise at 60 mph and you started a stopwatch when you passed a mile marker. When you pass the second mile marker your stopwatch should be at 60 seconds.