Low oil pressure after oil change? (1 Viewer)

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Hey mud,

Thought I’d try the Mobil 1 15w50 Synthetic from a couple threads here, oil pressure gauge reads low after ten minutes of idling. Any ideas? I cleaned out the connector on the sending unit, took the new yzdd3 oil filter off to verify it has oil...the gauge usually hangs out at the 2/3 mark with 15w40 and 10w30 regular dino oil that I’ve run previously.

Also noticed a knock knock sound from the flywheel cover...didn’t really notice this before, is this normal or am I just paranoid at this point?

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Spook50

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WAY WAY WAY too low viscosity. Good for new engines with way tighter tolerances, but bad news for 2Fs and 3FEs. My 3FE with 302K miles gets Mobil 1 High Mileage 10W-40 with one quart substituted for Marvel Mystery Oil and a K&N filter (really no reason to use a K&N over a Toyota filter; they're both very high quality, but the K&N has the hex part on top that lets you get a 1" socket on it to make removal and installation WAY easier). Oil pressure is right on the money and my valve train is nice and quiet (for an F engine anyway).

The low viscosity might explain your knock too. I'd change the oil out asap and see if that stops the knock.

Edit: pay no attention to the incoherent ramblings of the tired man.....
 
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Joined
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WAY WAY WAY too low viscosity. Good for new engines with way tighter tolerances, but bad news for 2Fs and 3FEs. My 3FE with 302K miles gets Mobil 1 High Mileage 10W-40 with one quart substituted for Marvel Mystery Oil and a K&N filter (really no reason to use a K&N over a Toyota filter; they're both very high quality, but the K&N has the hex part on top that lets you get a 1" socket on it to make removal and installation WAY easier). Oil pressure is right on the money and my valve train is nice and quiet (for an F engine anyway).

The low viscosity might explain your knock too. I'd change the oil out asap and see if that stops the knock.
Wait, really? I've been poking through oil threads on here and have found there's multiple instances of mudders trying out this oil...


@HemiAlex @Cruiserdrew any issues with your oil pressures?
 

Spook50

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Wait, really? I've been poking through oil threads on here and have found there's multiple instances of mudders trying out this oil...


@HemiAlex @Cruiserdrew any issues with your oil pressures?
Nevermind, I'm a tard. For some reason I read your oil weight and what registered in my head was 5W-20. I had been up for about 40 hours at that point.....
 

Hojack

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Drain and refill with conventional and see if you’ve still got a knock. Hopefully it goes away and your oil pressure gets back up to normal. Have you noticed any oil leaks? I tried straight synthetic in my 04 Dodge 3500 and after 1,000 miles noticed a few drips start to develop. Next oil change went back to conventional and they went away. I think it has to do with the synthetic molecules being the same size vs conventional where they vary.
I always ran 10W-30 Napa conventional in the 2F before the diesel swap with no problems. I heard Napa and Valvoline come from the same oil refinery, just Napa has a private label.
 

OSS

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I always thought that Mobil 15-50 stuff was too thick & syrupy. I tried it once and definitely felt a loss of power cuz of its thickness. I didn't like it. On the other hand, I know that Castrol 5W-50 Edge synthetic oil is the cat's meow for the 2F.. I used that stuff exclusively for 27 years. Zero problems. Cold startup fine even when freezing, works great in the blazing desert too. Excellent power and mileage. Zero sludge or varnish after 250,000 miles.
(As an expensive synthetic option)

Yes- it'll weep by OLD seals & make drips, but new seals & gaskets it won't leak past at all.
 

Seth S

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edit: consider picking up an oil pressure gage and reading the pressure at the engine....this way you can rule out the factory gage and get some real readings. I got an OTC pressure kit off of amazon that works well enough.
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I'd second changing your oil filter as its easy to do without dumping the oil. top off the oil level after to cover what was lost in the filter and see if there is any change. After that if no improvement dump the oil and go to what you used to run and see if there is any change.
 
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Thanks for the replies everyone. I swapped on my old Toyota filter and same result, pressure is still low. I’ll grab some Rotella which I normally run and swap it out this afternoon.

Just to verify, the connector clips on the middle of the sender, right?

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Hojack

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Thanks for the replies everyone. I swapped on my old Toyota filter and same result, pressure is still low. I’ll grab some Rotella which I normally run and swap it out this afternoon.

Just to verify, the connector clips on the middle of the sender, right?

View attachment 2102209
Smell ya later😆
 
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Realizing most oil replies are just personal stories and circumstances vary. I’ve had great luck with as thick as 20/50 on high mileage engines - 300,000 Miles plus.

I also don’t buy into the synthetic oil makes my engine leak theory. I’ve never had that and have flipped quite a few engines from conventional over to synthetic. If you s*** leaks, it leaks, either fix it or park on the street ;)
 

HemiAlex

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317,000 miles on mine. It burns about a quart in 3,000 miles and I’m sure it’s got a bad ring on #5. No leaks, but it drips once week from the front main seal. I won’t be touching it

I used conventional delvac 15w40 with riselone additive, 20w50 VR1 conventional and now Mobil 1 15w50 synthetic.
The best value is the mobil 1 for me. The 15w50 is highly regarded amongst euro crowds and it’s very high zinc. I’m able to string It out to 5k miles.

The real secret is the filter!

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Spook50

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Realizing most oil replies are just personal stories and circumstances vary. I’ve had great luck with as thick as 20/50 on high mileage engines - 300,000 Miles plus.

I also don’t buy into the synthetic oil makes my engine leak theory. I’ve never had that and have flipped quite a few engines from conventional over to synthetic. If you s*** leaks, it leaks, either fix it or park on the street ;)
It won't create leaks, but if you have minor leaks and worn gaskets that are otherwise covered with buildup from running dyno oil, the synthetic will wash that away over time and make the leaks known. That's the case with me, so at some point I need to do the oil pan gasket and valve cover gasket. I think there's some seepage from my side cover gasket too but it's really minor and a PITA to get to so I'm going to leave it alone for now.
 

Seth S

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It’s more that it will promote leaking in an engine that’s already got old seals and gaskets in it. If you do a reseal on the engine and switch to synthetic oil you should be fine.
 
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Real problem is that the synthetic has less friction (is more slippery) than conventional oil. The oil return lines in older engines are larger to get the oil back down to the pan but when using synthetic the oil drains back faster than with conventional oil. At low oil pump output, like at idle, this shows up as low oil pressure. i had this in a Lotus twin cam engine when I changed to synthetic. It never hurt the engine over long time use. Oil pressure comes up when rpm and oil pump output increases. I wouldn’t worry about it.
 

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