when I bought my '02 2500HD a month ago I was told that it was 'chipped', but nobody knew how.
Anyway, I drove it for a couple of weeks and I worked out that I was getting about 16-17mpg's around town.
The other week I took it to the local GMC dealer and had it re flashed to factory settings, as I really did not like the idea of not knowing how it was programmed.
Driving it after the re flash, I really could not feel any difference in the overall performance, but to my surprise, my mpg's went up to 18+ around town, have not yet had a chance to do hwy......now thats quite a difference!! It will be interesting to see how it goes in the coming weeks.
I am also having all 8 injectors replaced, as they are still the original ones and two are off the scale and a couple of others are going that way, truck has just over 100k miles, so wonder if that will make a difference in the mpg's as well!
Anyway, I drove it for a couple of weeks and I worked out that I was getting about 16-17mpg's around town.
The other week I took it to the local GMC dealer and had it re flashed to factory settings, as I really did not like the idea of not knowing how it was programmed.
Driving it after the re flash, I really could not feel any difference in the overall performance, but to my surprise, my mpg's went up to 18+ around town, have not yet had a chance to do hwy......now thats quite a difference!! It will be interesting to see how it goes in the coming weeks.
I am also having all 8 injectors replaced, as they are still the original ones and two are off the scale and a couple of others are going that way, truck has just over 100k miles, so wonder if that will make a difference in the mpg's as well!
