1998 gmc 3500 6.5 td bucking

[tltowing]

hi all i have a problem i cant solve.when i go down the highway at like 65-70 it bucks like its not getting fuel,so far i replaced the pmd (put it on a cooler).did that 2 times cant be bad.than i replaced the fuel filter and it was fixed.about 300 miles later it started to buck again so i replaced the filter again.ok fixed ya right another 300 miles later bucking again.so than i checked the lift pump that is good, than i replaced the filter again.at that time i took the old one apart nothing in it not plugged clean like new.than i tried to drain the filter bowl nothing came out of the valve????but i cracked the bleeder on top of the filter it squirted out and hit the hood, so i put the new filter in and it was fine for 300 or so miles can someone help????

[More Power]

Sounds like the lift pump could be intermittent.

Jim

[ToddMeister]

Or the oil pressure switch contacts powering the lift pump could be intermittent, too?

[bl78ljb]

Check out the below thread for other ideas as well.

http://www.thedieselpageforums.com/t...ad.php?t=29697