(Lots of people use this but I found out about it a couple of years ago when Tony said he used it. Thanks Tony.) Blackstone Laboratories oil analysis. It's not the law, just a good idea. You can see how things are wearing in the engine and maybe catch a problem before it's catastrophic. If you're interested in cost savings by running your oil and/or filter longer this will tell you just how long you can go. If you're interested in seeing just how alternative oils perform this will tell you. You can send notes with it as to what you're mainly interested in and they will comment on it. My last comment was "Oil changed every 3K so only interested in engine wear and oil performance". They didn't suggest that I could run my oil longer than I do this time. You can have them send you free sample bottles and mailers and pay each time you send it in or you can pre-pay (pre-pay for 6 samples or so and you get a couple of bucks off each one). It's very reasonable. You get a plastic sample bottle that's about an ounce or more, a printed label to include, a little ziplock baggie that fits the sample bottle, a larger bottle/container that the baggied sample bottle fits neatly into. The outer bottle has a mailing label on it. You print out the letter they have to explain that everything has been USPS approved and meets USPS hazardous materials requirements (you will need this to hand to the postal clerk who is going "I don't think so...".). About a day after they receive it they will mail you a hard copy and/or send you email with a pdf. You can go on their site and look at your reports there too. Sample procedure: You should take the sample after running the engine for about 15 minutes. It's fine to let it cool down. You don't take it right after starting it because there's liable to be some gas blowby at startup on a cold engine. Getting it up to operating temp will evaporate any condensation as well. If you take the sample while changing your oil, let some drain first and sample in the middle somewhere (just like peeing in a cup). For $25 they have a really nice oil pump. Sample bottle screws right on the pump. You shove the tube down the dipstick hole and pump right into the sample bottle. Very neat and tidy. Tube can be cleaned with a little kerosene (won't contaminate the next sample -- I guess they mix it with kerosene to analyze it so no problems). Here's what you get back.
