Ok i just recently purchased a 2001 silverado 2500hd with the 6.0 with 120k miles on it. When the truck is between an 1/8 and a 1/4 a tank of gas in it the truck will sit there crank crank for maybe 15-20 seconds, then il stop cranking and after that it fires up the first crank. I just recently fully filed the truck up and so far no problems yet. Ive looked for other people who have had this issue they say it sounds like a fuel pump but im curious what could be causing this starting issue because ive owned 99 suburban 5.7 292k miles and 93 silverado 5.7 182k miles and never had any issues with hesitation at crank with that much fuel in it. I am new to the new LS based vortec engines (6.0, 5.3, 4.8) so any help will be appreciated
