NOISY valve lifter(s) or rocker arm(s)

My 02 Olds Intrique has been displaying signs of either a noisy lifter (s) or perhaps a worn rocker arm. I bought the car used back in late Feb '04 and noticed the sound shortly after. The noise was less noticable during the summer and fall due to warm temps. however now that the winter weather (COLD) has arrived its really clattering at start up . I suspect that its a lifter thats not holding its oil pressure and leaking down, or maybe a worn or faulty rocker arm . I heard that the rockers are Alum.. and could be the cause. the key here is temp as things metal will expand and contract.
My question is > Has anybody experienced similiar problems with there
Olds Intrique in reguards to noisy lifters on cold startups, and if so , were they able to get it fixed under warranty from there GM dealer.

> Arte-Marte (Canada)

my dad had this problem. Make sure you use 5W30 and not 10W30 oil. Make sure there is enough oil in the engine. My dad added 1 quart of Amsoil 0W synthetic (added when the engine was one quart low) and the noise went away. The rattling would go on at startup for 3-5 minutes then go away. My dad was using 5W30 and had the problem.

Amsoil and Mobil 1 are the only true synthetic oils I know about. Castrol Syntec is a cracked (split oil molecule by electricity) motor oil and not a true synthetic.

Are you taslking about a valvetrain noise or piston slap with a cold engine?

The noise in question is in the valvetrain. Its at its worst at cold start up especially when outside temp is below zero degrees ( 32F ). The noise is fainiest after car reaches operating temp.

We used to add a can of auto trans fluid to the engine crankcase to sometimes quiet or clean a noisy lifter. (in volkswagens w/hydraulic lifters). I guess it's worth a try on the Intrigue. Don't overfill, though. We also used to add trans fluid to the fuel on diesel jettas and golfs, too. It would help lube and clean the injection pumps.

> We used to add a can of auto trans fluid to the engine crankcase to sometimes quiet or clean a noisy lifter. <

I have heard of this as a generic fix (not specific to VW's. Never tried it though.