On the NAV, is there a way to look at the speed via GPS? I'm asking this because I switched to winter tire on 17" wheels and they are smaller so my speedometer isn't correct anymore. Time for me to buy a programmer I think!

On a side note... now I must be very cautious because now it is way much easier to spin tires....

 

I have a Garmin hand held GPS that will do this but I don't believe you can do it with the factory GPS.

 

if you have a droid phone or a i phone i am sure you can download a app that has it built in.

 

I have a droid incredible and I use a free app called speedview. Gps speed and it can do 0-60 times as well.