i have an 06 GMC 4.3 with a 5speed standard. when i drive about 65 the son of a bitch starts jumping like i let off the gas and downshift and pop the clutch almost but i'm not doing that...i'm giving it steady gas and not letting off or hammering on it, just cruising at about 65. i'd say in about a 15 mile stretch on the way home tonite it did it about 10 times, its done it before but only once and it wasnt bad, also i think my 1st gear syncronizer is going out because at a dead stop its hard to get in 1st gear, oh and by the way, truck only has 15,000 miles on it, please let me know what yall think

 

Take it to the dealer!!! You most likely have some sort of internal problem with the clutch to make it buck like that. I would have them put me a new tranny and clutch in ASAP

 

bringing it to the dealer tomorrow morning, was checking all fluids last night and saw that the rearend had been leaking, i was so pissed off i didn't check it, i hope it at least makes it there

 

got it back from the dealer just now, drives 10x better, all they did was drop the tranny and look at the clutch and it was fine they said. they told me nothing at all was wrong with it but they went ahead and adjusted the clutch pedal and rebled the system, hell who knows, but its driving good for now, so we'll see