metal in oil

2001 silverado with 5.3. was changing the oil and when i pulled the drain plug, which has a magnet on it, there was like a metal sludge stuck to the magnet. the amount on the plug was about the size of the plug itself. wiped it off on a paper towel and using the plug i could pick the towel up so it is metal. im thinking it is cast metal because you cant see the particles. ive owned it for 2 years and every other oil change has been clean. so i drove it for 1000 miles and changed it again. same thing. cut filter open and ran a magnet through it. there is tiny tiny pieces of cast metal or very fine metal. in it. so my question is does anyone know where it may be coming from? the dealership said theyve never had a 5.3 opened up so they didnt know anything. the engine doesnt miss and i dont notice any loss in power. it does tick at idle at first start up even on a hot day. and it the winter it has a lot of piston slap. btw i run mobil 1 5-30 and wix filter. thanks for any help!

All these LS engines make some noise. There is no reason to be worried about metal sludge on the magnet. In fact, they don't have magnetic drain plugs any more so people won't worry. If there was a problem, you'd know it soon.

On the other hand....I have a 20007 2500 6.0 with a wasted cam right now that has perfectly clean oil than been in it for a few weeks.

So you are saying the amount of metal "sludge" on the magnet was the same size as the bolt? or the same size as the magnet tip? If it is the later, I agree with Guzzler, normal! if you have more than that I would suspect you will be stranded soon. Either way you will find out if it is serious or not within the next 1k miles!

valvesprings fret off a lot of metal, too. If you put new ones in your next couple of oil changes get to be nasty.

I have a magnet on my drain plug, and have never any metal in my oil. But I use amsoil.

I Would do a tune up on it, just to be safe.