Hooked up my Edge last week and everything works great except for the speedo calibration. I have 35's but no matter what parameter I set the Edge to it does not change my speed reading. I have set it at 2300 all the way up to 2800 and none of the settings effect the speedo reading. What am I doing wrong? The gear ratio is set correctly at 3.73. Driving beside my wife on the highway, hers correctly reads 65 and mine reads 59 on the Edge and speedometer. It reads 59 set at 2300mm and at 2800mm.

 

Read this and follow the instructions for custom settings: https://www.f150online.com/forums/ch...ions-menu.html

Here's another thread: https://www.f150online.com/forums/ch...tion-help.html

And another: https://www.f150online.com/forums/ch...tire-size.html

 

Thanks, I had already read those. Still don't see anything (unless I'm completely looking over something) that will address my problem.

 

When you go to the custom options menu and load previous settings, what values are in there for TS and GR?

 

Shotgunz - Think I figured out what i was doing wrong. After setting the tire size, I wasn't setting the "Done" setting. I was just setting the tire size and then pushing "Enter" and back to main menu. I'll drive it again this evening and see but I feel that was the problem. Thanks.

 

Good to hear. That's exactly what I was thinking and why I asked about load previous settings.

If you change other values in the future, make sure you follow the sticky's advice/procedure.

 

If you weren't scrolling to "done" when you finished putting in all your settings, you weren't actually programming your PCM! This is what we mean by "backing out" of the custom menu.

With 35 inch tires, I'd try a Tire Size of 2709mm.

- Jack

 

2710 is what i entered. I'll try it out this evening.

 

Best way to verify accuracy is with a GPS.

 

That would be great... if I had one.

Everything is up to snuff now. 2707mm gets me where it needed to be.

 

You can use Google maps or mile markers and drive a known distance (preferably 10+ miles; longer is better). Then use the following formula:

Known distance (or GPS odometer)/truck odometer x old circumference (or revs/mile) = new (meaning corrected) circumference (or revs/mile)