Priming your oil filter when doing an oil change.

tacojoel

Well-Known Member
I always fill my oil filter first before installing it when doing an oil change. I can't believe how many people say this is a bad idea. We've proven on a dyno it takes a few seconds for the oil pressure to come up if you start with a dry filter. This causes excessive wear/scratch's on the crankshaft main bearings, as they will momentarily touch together due to no oil film that can protect this. Filling the oil filter, and starting the engine will deliver oil pressure instantly. I just thought I'd give others this tip if their installing a dry filter like shown in so many oil change videos..
 
umm yeah there would be oil film (albeit minimal) left from oil change unless this 0W synthetic completely drains and leaves it all dry, which i would doubt but IDK

my rig the oil filter is at an awkward upward angle so cannot really prefill without backDrain and making a much bigger mess than needs to be around the area and onto the splash shield undercovers

i doubt that the monkey changers at the dealer doing my rig OCI the past 27 years have EVER prefilled it but who would know but them, right?
 
Whether synthetic oil, or not makes no difference. Your last oil change isn't really enough to protect these bearings from some type of wear. I think toyota purposely made the oil filter canister upright on their 3.5 engine knowing this.
 
Yep, but there's still many do it yourselfers, and video's that don't practice this, yet they gotta change their oil 2-3 times sooner than it needs to be. Little to they know not filling their oil filter every time is likely doing more harm than good. Would you want to wait 5 seconds for your engines oil pressure to come up every time you install a dry oil filter? Where's our toyota god on this?
 
i don't even have a clue HOW the oil gets into the filter from the engine when it is running and circulating :confused:

gen2 v6 the filter is on the top of the engine
 
Oil pressure begin's as soon as you start turning the crankshaft via the starter. The crankshaft turns the oil pump which in turns supplies oil pressure to all the various critical engine internals. When no oil is supplied even for a few seconds, thats when engine wear is most likely to take place.
 
I always pre-fill the new fuel filter on my diesel tractor, to prevent an injector airlock. But never tried to do that to a new oil filter on my 2nd gen 4.0 V6. As Jay said, the oil filter is upside down so it is rather impossible to attach it full of oil to the engine. I do remember my old '01 1st gen Taco having the more conventional oil filter with the attachment up, but don't remember anyone saying it was important to pre-fill when spinning it on. I do think the "upside down" oil filter makes for a much less messy change-out, as long as you allow the engine to be idle for a time to allow the filter to drain on its own.
 
you must've had the 4 cyl Gen1?
I always pre-fill the new fuel filter on my diesel tractor, to prevent an injector airlock. But never tried to do that to a new oil filter on my 2nd gen 4.0 V6. As Jay said, the oil filter is upside down so it is rather impossible to attach it full of oil to the engine. I do remember my old '01 1st gen Taco having the more conventional oil filter with the attachment up, but don't remember anyone saying it was important to pre-fill when spinning it on. I do think the "upside down" oil filter makes for a much less messy change-out, as long as you allow the engine to be idle for a time to allow the filter to drain on its own.
 
I could never see an upside down oil filter as on the 4.0 unless the oil pump is in a location that doesn't matter. I had small block chevy's, and pontiac engines....I always filled the oil filters first if doing an oil change. My tundra 4.7 was a pita with a horizontal mounted filter...I'd fill it partially not to make a mess when having to install it back.
 
My 5vzfe six cylinder filter is slanted downwards
Always dribbles upon removal all over the center splash shield if it is still attached
 

It's a bit hard for me to imagine, but quite a few people out there shouldn't be changing their vehicle's oil and filter.
When my brother first tried to service his '60 Biscayne, he drained the manual transmission 'grease' by mistake (ignorance).
Some folks simply have zero mechanical ability.
 
Yeah, I've got friend like that. He's a chemist working for a plant down in texas. Before he got a locative job there, he work at a local company here. Smart as all hell mathematically, but place a tool in his hand to remove a carburetor, and he'll seriously hurt himself.
Imo, lack of mechanical ability is one thing, stupidity is another. If both, thats a real problem.
 
I’ve always filled my oil filters before installing them. That’s the way I was taught. I’ve never heard of putting a dry filter on. If people want to do that to their vehicles that’s their choice. Why someone would do that is a mystery to me.
 
Are you letting the oil weep out of the hole for days on end before plugging it back up to fill the crankcase
 
Can't. My filter is on the top of the engine and open end down. It'd make a horrible mess at install.
 
I prefer soft flour shell Tacos. Not exactly sure how to put taco on a rotisserie. Each Thanksgiving I put the turkey on the rotisserie then into the Weber grill. Much better than in a roaster in the oven.
 
My best mate who is a Master Honda Tech with over 20 years experience says he doesn't prime the filters.
 
Back
Top