Speedometer off by 7-8 kph

[Stumph]

Just bought my 08 g35x and noticed the speedometer is not right.
No mods, factory tires & rims. Is this a commen issue? I've read in other forums that I'm not alone.
Anyone know what the issue could be? I called my dealership and he is looking into it. I'm afraid he's not going to be able to do anything under warranty?
Car has less then 60k in kilometers and I'm assuming it prolly less then 50k cause speedo is out by %5-6. 100kph down the freeway and gps is reading 94kph. I used 2 different gps and both where dead on.
any input would be great!?

[joe603]

Welcome to NICO!

I think there is an adjustment you can do on the ECU. Check out the G-FAQs page to get into the diagnostics menu.

[telcoman]

Just bought my 08 g35x and noticed the speedometer is not right.
No mods, factory tires & rims. Is this a commen issue? I've read in other forums that I'm not alone.
Anyone know what the issue could be? I called my dealership and he is looking into it. I'm afraid he's not going to be able to do anything under warranty?
Car has less then 60k in kilometers and I'm assuming it prolly less then 50k cause speedo is out by %5-6. 100kph down the freeway and gps is reading 94kph. I used 2 different gps and both where dead on.
any input would be great!?

I see a difference by a few MPH on my G between the speedometer and the GPS also.
It doesn't bother me and could in the future perhaps provide some doubt in the case of a speeding ticket.
The question I have is how does the GPS speed calculation compare with radar?

Anyone know a friendly cop that is willing to perform some testing?

Telcoman

[Stumph]

Gps is more accurate then radar I would assume. Gps works based on triangulation of sadilite vs a radar gun that would have to be calibrated properly. (more room for human error)

Regardless my spedometer is off by 7% thus my odometer is also reading 7% higher then actual km on the car! I've gotten no response from my dealership as of yet

Also there are no adjustments that we can make to calibrate the spedo that I'm aware of? Dealership fix forsure! I'll post an update as I get em.

[audtatious]

If you have navigation there is a speed adjustment in there. It probably just adjusts the way the navigation system is working tho as I've never tried it.

http://moodym.com/articles/diag/hidden-diag.shtml

confirmation/adjustment screen
navigation screen