question on a 2500 Seirra 6.0

[teamjnz]

Hi Friends,

I am new to this forum. I just bought a used 2000 Seirra 2500 4X4 X-cab long bed with the 6.0L and 3.73 rearend. I started it up this morning and the engine had a knocking sound . It went away after it warmed up. I have heard of something called "piston slap". Could this sound be piston slap? Is it bad?

 

I am also interested in what the performance numbers are. What is the horsepower and at what RPM? What is the maximum torque at what RPM?

[gave20]

Your a likely canidate for piston slap, Cold Start Knock (CSK) or not detrimental just awful sounding ( GM's solution). How many miles are on it? I would think you would have aquired CSk before now, if it was cold out it could have been lifter noise? As far as HP and TQ #'s my 04 makes 300HP at 4400 and 360TQ at 4000 so your #'s will be a bit lower but that should give you ball park.

 

Dyno curve

[BDBWTE]

Fear not that is just the Piston Slap you've been informed of. Mine does it sometimes and others doesn't ahh oh well no probs here.