Speedometer and Odometer error corrected easily

I read through some of your math, but could not put together a formula to find the right gear for the 285/70 R17 tires I am running. When I am at 65 on my speedo, I am actually going closer to 70. I have done a speedo cable gear change on my old explorer before, but a forum I belonged to had a gear calculator that was put together by a member.

Could you post the formula you used? Having an accurate speedo would be nice. I know I need to go down in size on the gear.

 

Do you know where to buy the gears?

 

I think all car makers ( bump up) the speedo a tad to get those mpg readings they want to see. I run 285s on stock gears and am barely off. When I had stock tires I would drive by a radar and read 5mph more than radar read. Now with the 285s I'm 1-2 mph slower than radar reading.

 

Based on the part number above, dealer will have it. Try Camelback.
http://parts.camelbacktoyota.com/pa...make=Toyota&action=oePartSearch&siteid=214329

 

Thank you, I guess I missed that comment.

 

Or to reduce their warranty liability duration

 

Just found this thread. I have been interested in fixing my odometer since I re-geard to 4:56 and have 255/85/16 tires (tall 33's). I know there is an inline module by Hypertech but that is $200+ for a simple calibrator that I could probably make with an Arduino for $70.

I may consider changing gears to just get a more accurate odometer. My odometer reads more miles due to my gear/ tire combo.

Awesome Thread.

 

Hmmm. You may be looking a long time for the gear to replace. My '14 6-speed does not use the sensor described in this thread. There is simply a blank plug where the sensor use to be. This probably started back with the '09s when Toy decided to radically increase the use of electronics.

 

,wA

 

How accurate is those what your speed is going on the road?