Low oil pressure....sometimes

[SnowDrifter]

Let me chime in on the o ring test real quick

The o-ring is situated about level with the pan

The pan in these things are pretty large

2qt over will not appropriately raise the level, nor will a slight difference in angle introduced by jacking the rear end push enough oil to the front.

Consider the height of the oil level sensor in this diagram and the shape of the pan. I think that'll clarify why an extra quart or 2 is negligible. That much of an overfill would also allow the crank to dip into the oil and why it's not recommended to run it for more than a few seconds. If you experience the issue when hot, run the engine until hot, overfill, run again, get your numbers, then turn off





if you want to see just how much the pan holds, pull the dipstick tube out and dump oil in until it runs out that hole like a diff

Edit: Fixed picture

Edit again: If someone has access to cheap oil and would be willing to yank the dipstick and note how many quarts is needed to overflow the hole, that would be sweet.

 

[Rocket Man]

Let me chime in on the o ring test real quick

The o-ring is situated about level with the pan

The pan in these things are pretty large

2qt over will not appropriately raise the level, nor will a slight difference in angle introduced by jacking the rear end push enough oil to the front.

Consider the height of the oil level sensor in this diagram and the shape of the pan. I think that'll clarify why an extra quart or 2 is negligible. That much of an overfill would also allow the crank to dip into the oil and why it's not recommended to run it for more than a few seconds. If you experience the issue when hot, run the engine until hot, overfill, run again, get your numbers, then turn off

View attachment 229147



if you want to see just how much the pan holds, pull the dipstick tube out and dump oil in until it runs out that hole like a diff

Edit: Fixed picture

Edit again: If someone has access to cheap oil and would be willing to yank the dipstick and note how many quarts is needed to overflow the hole, that would be sweet.

Be advised the dipstick tube is corroded on many of these model years and pulling it out may very well end up with a piece of this corroded tube still stuck in the hole. It is NOT easy to get this piece out if that is the case. I know this from experience. FYI I’m in the Pacific NW where rust is never an issue either.Proceed at your own risk.

 

[SnowDrifter]

Yeah I didn't consider the rust issue. Not an issue where I am!

 

[Rocket Man]

Me

Yeah I didn't consider the rust issue. Not an issue where I am!

Me neither but that was the only thing on my truck that rusted. Weird.

 

[iamdub]

Be advised the dipstick tube is corroded on many of these model years and pulling it out may very well end up with a piece of this corroded tube still stuck in the hole. It is NOT easy to get this piece out if that is the case. I know this from experience. FYI I’m in the Pacific NW where rust is never an issue either.Proceed at your own risk.

Good point and I'll third this. Rust is virtually non-existent here as well and the tube in my brother's truck snapped just past the flare. I'm guessing it's slow and mild corrosion from dissimilar metals.

 

[iamdub]

Let me chime in on the o ring test real quick

The o-ring is situated about level with the pan

The pan in these things are pretty large

2qt over will not appropriately raise the level, nor will a slight difference in angle introduced by jacking the rear end push enough oil to the front.

Consider the height of the oil level sensor in this diagram and the shape of the pan. I think that'll clarify why an extra quart or 2 is negligible. That much of an overfill would also allow the crank to dip into the oil and why it's not recommended to run it for more than a few seconds. If you experience the issue when hot, run the engine until hot, overfill, run again, get your numbers, then turn off

View attachment 229147



if you want to see just how much the pan holds, pull the dipstick tube out and dump oil in until it runs out that hole like a diff

Edit: Fixed picture

Edit again: If someone has access to cheap oil and would be willing to yank the dipstick and note how many quarts is needed to overflow the hole, that would be sweet.

Studying that pic and holding my finger parallel with the pan at the sensor height (the approximate level of the oil at 6 quarts), I rotated my laptop until my finger was pointing just above the front of the flange (the approximate location of the O-ring). Totally a rough measurement and guess, but I'm thinking an extra quart or two and a 20-30° nose dive should reliably submerge the O-ring.

 

[HiHoeSilver]

Studying that pic and holding my finger parallel with the pan at the sensor height (the approximate level of the oil at 6 quarts), I rotated my laptop until my finger was pointing just above the front of the flange (the approximate location of the O-ring). Totally a rough measurement and guess, but I'm thinking an extra quart or two and a 20-30° nose dive should reliably submerge the O-ring.

Sounds legit and agrees with the conventional wisdom, so how do you explain Doug's experience? Not enough pitch?

 

[iamdub]

Sounds legit

I considered looking for a side pic of the oil pan and holding a protractor on my laptop screen to come up with a more accurate angle.

...so how do you explain Doug's experience? Not enough pitch?

That's my guess. I just don't see how submerging the O-ring WOULDN'T be a valid and reliable test. The key is determining an overfill amount and angle that guarantees it'll be submerged. I think nose-diving it is better than overfilling it by 3, 4, 5 or whatever quarts. If it were me, I'd do about 2 extra and pitch it.

 

[HiHoeSilver]

That's my guess. I just don't see how submerging the O-ring WOULDN'T be a valid and reliable test. The key is determining an overfill amount and angle that guarantees it'll be submerged. I think nose-diving it is better than overfilling it by 3, 4, 5 or whatever quarts. If it were me, I'd do about 2 extra and pitch it.

Isn't that what he did?

 

[SnowDrifter]

Studying that pic and holding my finger parallel with the pan at the sensor height (the approximate level of the oil at 6 quarts), I rotated my laptop until my finger was pointing just above the front of the flange (the approximate location of the O-ring). Totally a rough measurement and guess, but I'm thinking an extra quart or two and a 20-30° nose dive should reliably submerge the O-ring.

20-30 degree nosedive is steep as hell. 20 degrees is a 36% grade. Bear in mind that's a slight bit steeper than Baldwin street

Another consideration is that as soon as you turn the car on, oil's going to be out of the pan and circulating/dripping through the engine, which will cause the level to drop.

if anyone could get some detailed measurements of the pan, perhaps we could calculate the rough volume to fill it. I'd crawl under and do it myself but I don't have a tape measure with me