Personally I like the old fashion way plus you can inspect the drain plug magnet it you have one. It isn't a difficult task.
It's a fairly common method used on some marine engines. Works fine and the only thing I would want to know is if the dipstick tube on the 3x8 points down to the lowest part of the sump. If the tube doesn't end up at the very bottom of the pan, you are leaving more of the old oil in there than opening the drain plug will.
This is how I change my oil. I dont have a lift and its a pain to jack the car up - put it on stands etc..... I've had no problems and it works great. The thing about un screwing the drain plug that i hate is the huge rush of hot/ warm oil that comes out - gushing all over the floor... this way its much neater and keeps everything clean. To make sure get all the old oil out, I flush with a small bottle of clean oil ( cheap ) once i get clean clear-ish oil I fill with Castrol. I also dont have to worry about over tightening the drain plug... and causing a leak. I've seen that before. You can add & subtract oil so you get the perfect oil pressure as well, with out having to rely on the dip stick all the time.
I can buy your statements above except for the last one. It gives me the impression that you can't check the oil using the dip stick.
Been using a pump from Griot's for a while. Very useful if you have limited space or time. The straw that goes down the dipstick tube is 4' or 5' long, and always hits bottom. http://www.griotsgarage.com/product/car+maintenance/oil+changes/multi+fluid+extractor.do The only problem I see with the LiquidVac system is it looks too small for a 3 liter motor.
I've underfilled the car, and overfilled the car using the dip stick. I find that when you fill up the car, and start it keeping an eye on oil pressure helps from over filling. Using the dip stick works but often times once the oil is up to temp, you'll find out that the oil is way up the stick...
I've seen that once oil is up to temp ( depending on viscosity) the amout on the stick goes up and pressure goes down a bit.
Weird is right. When you pull the plug any residue slug will get flushed out using gravity. I work on industrial machines and very seldom does anyone ever change the oil. Change the filter and let it run. Most of the machines were built during WWII and still going strong. I really do not believe oil has a due date based on day's or month's but hours it has been used. Changing the filter is more important, it is made of paper and paper has a shelf life. A clogged filter restricts oil flow. Just my opinion you don't have to agree with it.
The dipstick reading will be different between hot & cold. The correct method for reading the dipstick is when the engine is warm immediately after switch off. That's all you need to do & reading it any other time is just going to confuse you.. Oil pressure will inevitably drop as the oil gets warmer (and therefore thinner) but this has nothing to do with oil level (unless the level is dangerously low & the pump is starving)
You are correlating two things that don't go together. The oil pressure is determined by the pump, relief valve and clearances not how much oil is in the sump. As long as the pickup tube is in the oil the pressure will be the same.
Sounds like some need a oil dipstick reading 101 course. Not to mention a oil pressure refresher course.
Interesting observation. It reminds me of the time a car restorer freind rented a old building that was previously used as an engine rebuilding shop. It had a hot oil tank holding several hundred gallons of old, nasty looking oil. He also found several cases of oil filters in the back. Rather than draining the old oil, going to the pain of getting rid of it, and then buying new oil, he rigged up an electric pump with a old Fram duel oil filter setup, and started recycling the oil. Every few hours, he changed the filters and about a week later, the old oil was clear. Now, I'm not saying we should all stop changing oil and only change the filter, but the above did demonstate to me how important the filter is. Your mileage may vary....
Many fleet vehicles never change the oil. They use filters like one of the big Gullf Coast filters, monitor the oil with periodic oil analysis, and add oil when necessary and change the filter element periodically. Those vehicles put on more hours in a month than probably any of our cars do in a year.
I change my oil regularly of course. But sometimes I wonder, whether it's necessary, because the 308 engines have such an oil consumption, that you're constantly filling up with fresh oil. What if one would only change the oil filter and rely on the top ups with fresh oil ? Best Regards from Germany Martin
