Hey guys I have a 99 silverado 4x4 4.8L with 109,000miles, I bought the truck around this time last year and noticed that it shifted hard from 1st to 2nd and then just bogs down shortly after (you can hear it in the exhaust and feel it in the gas pedal) you have to punch the gas to get it going up hills, other than that it runs fine. the problem has not gotten any worse or any better in a years time and i finally just want to get this problem solved. If anyone has any ideas let me know, thanks