04 hoe is ticking.... Help

[Superman04]

So recently my 04 tahoe hit the 100k mark I do all the maintnence oil filter ectect but just recently been hearing a ticking noise on the passenger side of the engine but only does it idling after sitting so long like overnight or shopping but goes away after running for a few minutes currently running part synthetic high mileage castrol and lucas additive .oil and fuel treatment... Is it normal is it a lifter going out I just spent money putting 40 series flowmasters from 50s and a CAI runs incrediable being 100k plus just that damn ticking ugh

 

[Superman04]

Also I use to run regular oil in it had no issue but maybe that was hiding tje tick noise should I switch back or is it to late using part synthetic

 

[Tug boat]

I have a 2002 GMC 5.3 and a 2000 tahoe one with 255.000 and the other with 166,000 miles both of them do it we you cold start them but once they run for a min it goes away. I have a friend who works for GM and he says it the Famous GM tick lol lol he said its the way the 5.3 are made it takes a sec for the oil to get to the top. Mine have done it since I have owned them NEW. They do it worse in the WINTER. I useally start it and let it sit and run for a min and let the idel come down before I take off plus it lets the eng get worm which is better on any motor.

 

[clkelley]

This is a cold starting issue attributed to the oil. After sitting, the oil is not coating the lifters well enough, and in some cases, the oil isn't designed properly and doesn't eliminate the ticking when warm. IF they are in good mechanical repair with no visible leaks, you may want to try synthetic if not already using it. And possibly a "Pre-oiler" system to lube the valve train before start up...