2014 Impala-Speedometers show different values
 

I bought a 2014 Silver Ice Metallic Impala LTZ last August. I'm very happy with the car and sort of enjoy the 2nd looks and compliments I get about it. Best ride ever and exremely quite. So many things to like and only a few bothersome items. One that drives me crazy is that the analog speedometer shows a noticeably different value than the digital speedometer. Based on some of the highway speed displays I drive past, the digital appears to be the one that's accurate and the analog is 2mph faster. Not the end of the world but it truly does annoy me. I would have been happy with just one speedometer but since Chevy went to the trouble to install two, I'd like them to both give me the same value. I asked my dealer service rep about it and he said there's no adjustment or calibration and +/- 2mph is standard. I have a 2011 Equinox and both are EXACTLY the same. So my QUESTIONS are: Is it true that the speedometers cannot be adjusted or calibrated to display the same value? and.. Is it reasonable to want both to read the same or am I expecting too much? If they can't be adjusted, what's the alternative. New analog speedometer?

Turn off the digital. You can change what is in the cluster view. Problem solved.

Thanks Sledge. Kinda silly. I hope I get some real answers.

Which size tires do you have? 19 or 20"?


I haven't checked to see if the 19" are the same size diameter as the 20".

Maybe one of yours is mis-programmed to the wrong tire size.

Unless GM changed the way things have been done that past 15-20 years both displays would be driven electronically.


While it is possible it is highly unlikely GM engineered the car with a sensor for each display.

Mine is an LTZ with Adaptive Cruise and 20" Wheels.

No noticeable difference between the 2 displays but I use the IP display for other info 99% of the time.

Looking through tirerack.com, the 19" tires have a diameter of 27.7" and rotate 755 revolutions/mile, the 20" tires have a diameter of 28.7" and rotate 729 revolutions/mile.

My Impala has 19" tires.

The dealer service dept. wouldn't even take it out on the road to look at it. I didn't push the matter however maybe a different dealer would. I'd love to have a response from Chevrolet Customer Service to see if the speedometer inaccuracy is something that should be fixed. I think it should as I paid lots of hard earned $ for this "almost" perfect car.

is it consistently off by 2 mph? or just accelerating? decelerating?

going slow ? going fast?

on my 20" tires, the worst i saw was about 1 mph difference.

I took some video and tried to drive different speeds.. I'll post it when i get a chance later on.

btw, how tall are you?

why? do you think it a parallax line of sight error?