i've got an '01 2500 hd with a hyperpac chip and 4 in exhaust. the problem is that when the truck is under 1/2 throttle or more third gear winds out and doesnt shift to fourth until it about 3-5 sec or until i let out of the throttle. and if it stays in gear too long without shifting, it throws a "fuel leak-large fuel leak" code. any ideas???

maybe fuel filter or defueling because of programmer

it does need a fuel filter, but why would it shift odd only from 3rd to 4th, and not the other gears. and when it does finally shift, its like a nitrous shot coming in 4th. so it acts like its getting plenty of fuel. it also seems like its getting progressivly worse. i'm going to change the fuel filter today to see if that changes anything.

it does need a fuel filter, but why would it shift odd only from 3rd to 4th, and not the other gears. and when it does finally shift, its like a nitrous shot coming in 4th. so it acts like its getting plenty of fuel. it also seems like its getting progressivly worse. i'm going to change the fuel filter today to see if that changes anything.

hmm it could be the filter. change it and tell us how it goes and post a pic up of the filter.

just wanted to update. fuel filter fixed it!!! worst looking filter i've ever changed. it was so bad that it was starting to collapse on itself. thanks for all the help!!!

hey no problem. how many miles did you have on the filter??

not sure on exact milage. i'm thinking it was around 30,000 mi.

30k on the filter?!?

yea. i know, i need to shorten up on my intervals.

just a little, i know the gm fuel filter countdown is based on a 15k mileage. i do it every 10ish