Join Date: Aug 2006
Location: Arlington, VA
Thanked 12 Times in 10 Posts
Rep Power: 11
The best time to change engine oil is after a hard run, when the motor is hot and most of the contaminants are suspended in the oil. Failing this opportunity, you need to run your engine until it's up to operating temp (or beyond, if you can), then change the oil.
Changing engine oil via a dipstick suction device is not a good long-term solution, as I found out after doing it for many years. You can't get all the oil out and, if sludge begins to form, you won't get it either.
So, my advice -- earned the hard way -- is to consider this device you have a short-term solution, especially with a new engine.
Think about fitting a real oil change system (like the XChanger) to the engine oil drain plug. I did, several years ago, and I can change my oil in 5 minutes flat (out and in) without getting all messy.