I just bought a 1 1/2 year old 2007 Grand Prix. It was originally made
for the US but has been brought into Canada and the mileage and speedo
changed from miles to kilometers.

I was told the car had 14,000 km, and that is what it said on the
display.
The "GM vehicle inquiry system" says the odometer conversion from US
to Canadian was done at 13,925 miles.
Is this just a typo? Is it possible to change from miles to kilometers
and keep the same value or does the system do the calculation
internally and display either miles or kilometers, depending on which
is selected?

I am assuming the "GM vehicle inquiry system" must display either the
word miles or kilometers and not both when it displays the information.