gm 6 liter engine


New Member
need info?
looking to buy a roadtrek from2003 to 2006,depending on deal, my question is on 2001 to 2005 gm trucks with 6 liter v8,gas.
have problem with piston slap syndrome,
is the 6 liter engine in roatrek van,made on express gm van,have the same troublesome 6 liter v8,with piston slap,or is the engine in the vans not the same as the ones in the trucks.
thank you :question:


Senior Member
Re: gm 6 liter engine

I have a 2001 GMC truck with 6L engine. I haven't noticed any 'piston slap', but then I'm not sure what that is. However, this vehicle had trouble pulling about 6500 pounds of trailer up hills. I understand that people with trucks later than 2001 don't seem to have this 'weakness' problem.

C Nash

Senior Member
Re: gm 6 liter engine

yes, some of the early 6.0 had a condition known as piston slap but, I have seen GM engines with this condition run for over a hundred thousand even though it is kind of annoying. I would not worry to much about it. It was pretty common in the old 327 and 265 after engine overhaul if the pistons were not kurled. Probably a conditioned caused by building the 6.0 a little loose for less friction thus better MPG AJMO