10-31-2017, 02:34 AM
Why don't you loosen your drain plug until oil is slowly flowing out through the threads until enough oil has come out so that you are at the middle of the sight-glass and from then on just replace the same amount as comes out?
Like some others have mentioned, my thinking has been clouded by two paradigms: 1) always warm the oil before draining, and 2) never trust the siteglass, always precisely measure the amount that you put in (which assumes that all old oil will drain out).
So, thanks to Postoak's suggestion, I think I'll measure how much comes out next time, and fill to the top of the siteglass while being mindful that it should take nearly all of that 4th quart. I'm still a little worried about relying on a measure of how much drains out, just because it seems like there's always some oil that won't drain out of the filter, and there's always some that's left in my drain pan that I have to wipe out with shop rags. Perhaps it's only a few ounces, though. It's good to hear that others do have confidence on the efficacy of the siteglass measure.
Like some others have mentioned, my thinking has been clouded by two paradigms: 1) always warm the oil before draining, and 2) never trust the siteglass, always precisely measure the amount that you put in (which assumes that all old oil will drain out).
So, thanks to Postoak's suggestion, I think I'll measure how much comes out next time, and fill to the top of the siteglass while being mindful that it should take nearly all of that 4th quart. I'm still a little worried about relying on a measure of how much drains out, just because it seems like there's always some oil that won't drain out of the filter, and there's always some that's left in my drain pan that I have to wipe out with shop rags. Perhaps it's only a few ounces, though. It's good to hear that others do have confidence on the efficacy of the siteglass measure.