I know this is something that comes down to personal taste or habit. I've always pre filled the filter on every oil change I can remember since doing my own, noone said to pre fill but seemed to make sence. Many don't for whatever reason.

In the big picture will it kill the engine not pre filling probably not but why speed up the wear?

These guys put it to the test. So everyone knows they also do oil analysis like Blackstone. I thought it was interesting. 🤔

 

A bit late here with a reply but I too found it an interesting topic and watched it all the way through, thinking it was just another "myth busting" presentation. Its encouraging pre-filling the oil filter is highly recommended!

I was already to ignore any advice claiming pre-filling was a bad idea, once read an article where Boeing engineers discovered about 50% of engine wear occurred in those first few seconds where it was turning without full designed oil pressure.

I've tried two different engine oil pre-oiling systems but had to abandon both due to issues with the accumulator cannister would increase in pressure to the point its relief valve would vent. Even after showing my installation photos to the vendors they had no explanation, said my installation looked right but couldn't offer any explanation?!

 

Been pre-filling oil filters for 43 years, and I change my own oil. Wear metals always looked good on reports. Lucky, maybe but I see no reason to change methods.

 

^^^Same here especially since beginning to do this with Blackstone Lab's testing results.

 

I prefill my filter when the filter is vertical however I do not prefill my filter when it is horizontal. My Accord and Dodge Ram are vertical while my F150 and Harley are horizontal. My boat filter is upside down so no prefilling.

 

I can't fathom that the volume of air in the filter being pushed through the system is good in any way. Where does that air go? Does some go to a cam chain tensioner? Does some go to a lifter or two or three? Does some go to cam bearings? On some of my older engines (older like from the `70s), pre-filling was the difference between a couple of main bearing clunks or not after each oil change.

I also have a hard time with the idea that the filter element's first exposure to oil is under pressure and in a hurry.

I pre-fill all of mine. If it's a vertical filter I fill it to the top, and as air bubbles work their way out I top it off. Gives me something to do while the old oil is draining. If it's a sideways filter, I fill it to the top once, and not very slowly. By the time it soaks in etc. there isn't enough in there to spill if I keep it turning while I convince the threads to engage.

I've only done a few upside-down filters in my life. For those I just pre-filled what looks like about 10% of the internal volume and let it sit and soak for a bit. When it came time to install, I just made sure to be quick about it. Didn't ever spill a drop. For that little amount of oil I don't know if it really helps any, but it feels like it does.

 

I've been prefilling my oil filters before installing for 70 years now. Also on the 99 Ranger pushrod 4.0L after installing its prefilled FL-1A, I disable the fuel pump by thumping & tripping the inertia switch, or disconnecting it so the engine or fuel pump won't run & wash the cylinder walls down while I crank the engine with the starter (but not for more than 15 seconds so not to overheat the starter) until the oil pressure light goes out, to reprime the oil pump, finish filling the filter & burping remaining air out of the oiling system before starting & running the engine to check for leaks. I too change the oil on a warmed up engine as we gat a faster more complete drain with hot oil & no empty filter high rpm on the restart to check for leaks.

On my 99 4.0L pushrod I also Must drain & refill the oil sump without delay first, then remove & install the prefilled filter without delay & then crank it to finish burping the system or it'll sound like a diesel for days after an oil & filter change.

This disabling the fuel pump & cranking the engine works to burp & fill cartridge type oil filters, or screw on filters that have the open end facing down or sideways like my 78 Merc Zypher 3.3L I6 or at a 45* angle like my 94 3.8L Taurus & can't be prefilled completely before installation without making a mess. EDIT: This also made for nice quiet restarts after a oil & filter service on the 3.3, 3.8 & 4.0L push rod engines. More thoughts for consideration.

 

I've occasionally thought about doing that, and did on older cars where the coil wire was easily accessible. I figure that the modern cars put op with a couple of hundred thousand miles of oil changes with dry filters and quick startups, so me doing things more nicely should allow me a little bit of grace in that regard. I just make sure they're all the way warmed up so they don't high-idle with their new oil and filter.