Wipe the dip stick off very, very, very well
Then pull a sample
Note the smell, put it on a white surface and look at it under light (air filter box sticker)
Exclusion criteria:
- Floating particles
- Burnt smell
- Dark enough to be confused with engine oil
- Milky in appearance
If none of those exist, you're good to change it!
Ideally, drop the pan. Filter change isn't strictly needed. The filter/pickup tube isn't a filter, so to speak. It's a screen - a rock-catcher, if you will, to grab any larger particles before they ruin the oil pump. But it doesn't really do much in the way of filtering the way we think of it. Not a bad idea, while you're in there, but it's not really a pat-on-the-back item.
Biggest thing you want to do is clean the magnets off in the bottom of the pan, get rid of all the metallic schmoo that exists.
While you're in there, get another pan magnet and stick it on as per TSB here:
https://ls1tech.com/forums/attachme...350568544-new-turbo-gxp-service-bulletin-.pdf
Once you're at a known good starting point, you can do future changes through the dipstick tube with a fluid extractor. I do mine that way once a year.
Expect to add 3 to 4 quarts of fluid after dropping the pan. Don't overfill - too much is just as bad as too little!