Oil Change Observation

I've changed oil on my cars for as long as I can remember. I changed the oil on the Boss 302 yesterday afternoon.

I've always just drained the pan, then replaced the bolt and moved onto changing the filter.

This time around I drained the pan, hand tightened the bolt and then changed the filter. I then went back to the pan bolt, removed it, and another cup or so of oil came out.

I guess there may be some type of vacuum in the system, and it gets relieved when you remove the filter?

Anyways, just thought I'd share to see if anyone else has had the same experience.

I'll be following the new steps from here on out to make sure I get as much of the used oil out as I can.

Changed it hot or cold?

Could just be oil draining off the sides of the pan. I leave the plug out the entire time I'm doing the oil change (one beer or so?). Even when I put the plug back in there is still a small trickle of oil coming out. I don't lose any sleep over it.

At least you only have one drain plug to worry about

Yes 250ml isn’t much considering the fresh stuff =5-9L.

I tend to leave the drain plug out for while I do other things.
My house lift isn’t Jiffy lube so I don’t have multiple cars waiting outside impatiently.

I also keep the drain plug off for a while, at least an hour.

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Originally Posted by RedSN

Changed it hot or cold?

Could just be oil draining off the sides of the pan. I leave the plug out the entire time I'm doing the oil change (one beer or so?). Even when I put the plug back in there is still a small trickle of oil coming out. I don't lose any sleep over it.

At least you only have one drain plug to worry about

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Oil was hot. When I put the plug back in, after initially draining it, there was literally a trickle coming out of the pan. The amount that came out of the pan after removing and replacing the filter was waaaaaay more than just a buildup of residual oil IMO. I won't lose sleep over it either, but will from now on add the extra step. :cheers:

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Originally Posted by Minaccia

I also keep the drain plug off for a while, at least an hour.

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I'd be curious if you tried my method to see if you have the same experience as myself or not. I imagine after an hour, you wouldn't even get any dripping coming out of the pan?

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Originally Posted by WidowrRacing

Yes 250ml isn’t much considering the fresh stuff =5-9L.

I tend to leave the drain plug out for while I do other things.
My house lift isn’t Jiffy lube so I don’t have multiple cars waiting outside impatiently.

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Ditto for me, though I need over 8L to fill mine. I just found it odd that after almost completely draining the pan, that there was more in it after I removed the filter.

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Originally Posted by Gr8Stang

…was waaaaaay more than just a buildup of residual oil IMO. :cheers:

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Good to know. Now you’ll pull the filter off before putting the drain plug back in ….like the rest of do :sarcasm:

I normally pull the filter while it's still draining so never noticed.

^Same here, especially if the filter is a top-mount, side mount, or attached to a cooler, anything tilted down shouldn’t matter. I also crack the cap or pull the stick before going underneath to allow better initial drainage.

Believe it or not even after an hour or so there is still a tiny bit of oil that wants to come out of the pan, it's not a drip but a very slow flow, lol.

Next time I do an oil change I'll drain the pan and also remove the oil filter while the plug is still off and see if an extra rush of oil comes out.

Quote:

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Originally Posted by Gr8Stang

I'd be curious if you tried my method to see if you have the same experience as myself or not. I imagine after an hour, you wouldn't even get any dripping coming out of the pan?

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[QUOTE=ZR;428766]I normally pull the filter while it's still draining so never noticed.[/QUOTE

I've always only had one oil catch basin, so have been forced to drain one at a time, and I've always just started with the oil pan. Guess now I'll start with the filter change first. :thumbsup: