N4HHE
Well-known member
Manufactures specify hot so dealers won't have to sit around waiting for the vehicle to cool. They specify something so as to give the impression of knowing more than you.Ummm... Correct me if I'm wrong, but aren't oil changes supposed to be done cold? Other than running the engine for a minute to stir it up a bit, which I wouldn't imagine would heat things up that much.
I find if sucking oil out the dipstick (as is common on Mercedes) then it's best done hot. Same amount comes out hot or cold but 5W-40 comes out several minutes faster hot.
Others such as Husaberg dirtbike and 2.2L Sonoma same quantity hot or cold. 2000 Avalon and 2007 Prius took more oil to refill after a cold drain than hot. So I conclude more old oil came out.
As for to notion of suspending sediment in hot oil, do you really want to distribute that all over your engine before draining? If sediment exists would you not rather have it concentrated at the bottom near the drain to be pushed out by cleaner oil above?