How do you tell the difference? It's a 02 tahoe with 140k 5.3. Only hear it on cold start. TIA!

 

probably piston slap when cold the piston is "shrunk" and as the motor warms up the walls swell a wee bit along with the piston to make a "snug" fit... if it was a funky lifter it would not go away warm it would only get worse because of the lowered idle PSI as engine temps go up... if it goes away when warm than just keep driving it... these ls motors dont die and you can expect another 100k out of it id be willing to bet the farm on it!