Im just curious to know how many miles/kms you guys get out of a tank of gas on a 02 3.8 gt or one like it... i checked today and i got about 530km out of a tank of gas, but most of it was highway driving.

21 miles to the gallon on my 2001 Pontiac Grand Prix SE

My '00 GTP got about 400 miles out of a tank. That too is highway miles from a long road trip. I recent the guages at the start of the trip and when I got home the computer said 29mpg. I'm going to complain in the least about that.
I'd say average though, 27mpg on highway and 21-23 around city.

I also have an '02 300M which has about the same size engine. And if you ask me, I think the grand prix gets better gas mileage.

mine usually gets about 350 to 400 per tank. Depending on how im driving

it ain't the miles per tank that counts, it's the miles per gallon that counts these days, every day. the best i get is 30mpg which at current prices is 10 cents a mile.

I see approximately 25-30 mpg depending on where i am driving, city or highway. In the city i've seen as low as 18mpg.

For me, the km per tank varies, because i drive in both the city and highway, but it ranges anywhere from 400-500km per full tank.

checked in 3 times in the past 2 months, net average 21mpg, that was awesome, especially considering the worst I saw was 19mpg and that included a night of street racing on that tank...