Chevrolet Repair: Loud Tappet Noise on my 2004 Tahoe, tappet noise, piston slap

Question
Recently, a loud tappet noise has started on my Chevy Tahoe with 92,000 miles when the engine is cold. It goes away upon warm up, but not until the engine is totally warm. I've changed oil to 5W30, and that seems to help, but the noise returns after 2000 miles.

Answer
Hey,

 Sounds like you have a stuck or sticking lifter.  If the noise comes and goes and can be rectified by freshining up the lubrication system you should make sure to check:

OIl pressure, low volume may not be filling the lifters properly
Do an engine clean. Seafoam works very well for cleaning deposits and gum from lifters.

 There is the possibility it isnt' valve train noise and has some piston slap from a bad skirt or wrist pin.

Wayne