My 2010 F-150 Lariat speedometer is reading fast. About 10%. It's an all stock truck I bought new. Currently has 41,000 miles on it with orignal tires and no other troubles at all. Can these speedometers be adjusted or do they have to be replaced?

Any Help Will be Appreciated

 

Factory settings tend to be 3-5% off, with the speedo usually reading faster than your actual speed. 10% seems high. What were you comparing the speedo to? GPS?
Also, what speeds were you checking this at?
You say that the truck is stock, but are your tires factory sized? What is your tire size?

The computer can be reprogrammed. The dealer will usually only change to accomodate other factory size offerings. Aftermarket hand held programmers will allow for additional changes, usually.

In the end, just be happy that it's 10% faster than actual speed, as the opposite could land you a pretty nice ticket.

 

The tire size is P265/60R18 which matches the label inside the drivers door. I am comparing it to a GPS that was right on the money with my previous 1998 F-150 and the roadside radar signs that display your current speed. I might be reading 42 MPH and the sign says 38. The faster the speed the bigger the difference. At 70 MPH I'm showing 80MPH.

 

Your dealer can calibrate it. It is all PCM controlled off of the speed sensor.

 

The other side of that is that his warranty is also 10% less than it should be.