Has anyone had an issue wiht there speed? i think mine is off @ 5 mph.
I have a MC 03' CVT and have to run it @ 80 to run wiht traffic that i know is not going over 75??

 

It's normal. Speedo will show you going 3 to 5 MPH faster than your actual speed. The faster you go, the higher that difference is.

Consider it a safety feature. There's a rumor up here that it's also a German law that speedos need to be calibrated to read "fast"

A few months ago I saw an article that tested speedos of various mfgs. ALL of them tended to read on the high side with the exception of those in GM vehicles which tended to be spot on.

 

Thanks, that figures i was driving next to my wife in her GMC and we were talking on the cell phone...

 

that sounds safe

 

I don't remember the precise formula, but a couple of years ago I remember finding the speedo calibration info. If memory serves it was something like:

Indicated speed = Actual speed * 1.05 + 2.5 MPH

so, even at low speeds 2.5 MPH is added on and the actual speed is increased 5%. 55 MPH would register as 60.25 MPH, 5 MPH would register as 7.75 MPH.

I'll see if I can track down the precise #'s for the formula (if anybody cares )

 

I care

 

It's true...a fact that does not seem to impress police though.

 

I thought my speedo was off too, until I got my GPS unit (Garmin eTrex Vista), which records the speed at which you are traveling, and it was dead-on with the big ol' speedo and the digital readout on the OBC. All three said I was traveling at 95MPH, during my test run.
Also, some highways have speedo test sections which mark off one mile. When you hit the start of the section, travel at 60 MPH, mark off one minute on the clock, and one mile on the odometer. It should match up to one mile per minute, matching 60 MPH.

 

While doing some open road racing, I was able to check my speedometer compared to radar, and the speedo reads about 3 mph fast at all speeds.