Drop in oil pressure

[Joseph Garcia]

Based on the feedback in this thread, I think I'm just going to keep driving it as is with no changes. I've read online that minimum oil pressure spec per GM is 10 PSI per 1k RPM, and if that's truly the case maybe I shouldn't worry about it until it drops below that threshold.

Good choice. One less thing to be concerned about.

 

[Matahoe]

One last thing...Make sure you are adding the proper amount of oil! With a PF-61e filter that would be somewhere close to 7 quarts! Your dipstick might be a non original as well. And also put on a ACDelco filter just to rule it out per the TSB from GM.

 

[clandr1]

One last thing...Make sure you are adding the proper amount of oil! With a PF-61e filter that would be somewhere close to 7 quarts! Your dipstick might be a non original as well. And also put on a ACDelco filter just to rule it out per the TSB from GM.

I'm not using a PF-61e. As stated earlier, I've been using ACDelco PF46E oil filters for at least 3 years. I'm the original owner and can guarantee the dipstick is original.

 

[SnowDrifter]

Chiming in on the gm oil pressure spec: it's useless.
10psi per 1k rpm is what... 5-6 psi at idle? If you went by that, you'll be looking for a new engine in short order. While I have nothing concrete to prove this, it's been my findings from a LOT of reading that ~25psi at idle is the lower limit for these engines before bad things start to happen.


For oil filters: A larger / higher flow filter might show an increase in oil pressure. The pressure sensor is located after the filter. Less pressure drop through filter -> more available to the rest of the engine (and sensor) before the bypass valve opens

On the dash reading: Our trucks definitely have one of the better oil pressure gauges - they will actually read pressure and not just exist as a fancy 'dummy light' as you see in the majority of vehicles. However, they aren't accurate enough to do diagnostics with. You'll really want a scan tool to check your numbers. If you have a bluetooth OBD reader and torque pro, I can show you how to set that up as it won't read natively.

I can't speak to if this is related to your issue, but... FWIW, I had some issues with mine actually having fluctuating oil pressure, particularly at higher RPMs. It wasn't the o-ring, but it was the oil pump. The bypass valve was oh-so-slightly binding in its bore, and there was also some minor cavitation wear on the pump gears. Since then, I've installed a new oil pump that has resolved that issue.

Oil-wise, I run some euro-spec 0w40 in my rig. Keeps it happy. Pressures are kind of moot since I have a different pump than factory, but my hot pressures are 47-50 at idle, 60-70 down the freeway.

 

[Matahoe]

I'm not using a PF-61e. As stated earlier, I've been using ACDelco PF46E oil filters for at least 3 years. I'm the original owner and can guarantee the dipstick is original.

The oil filters are interchangeable with respect to having same thread and width. The PF-61e just being longer and having more filter area.

 

[SnowDrifter]

The oil filters are interchangeable with respect to having same thread and width. The PF-61e just being longer and having more filter area.

Yep.
Years ago, I bugged one of the amsoil reps for sizes when I was sorting oil filters. While the chart they gave is specific for their product numbers, you can cross-reference to other brands. I've found it generally useful.

Amsoil​	Style​	Height​	O.D.​	Thread /​	Gask OD​	Gask ID​	By-pass​	Drainback​
± .06​	± .03​	I.D.​	± .02​	± .02​
EA15K01	cartridge​	2.31​	2.48​	1.13​	NA​	NA​	NA​	NA​
EA15K02	cartridge​	2.70​	2.8​	1.12​	NA​	NA​	NA​	NA​
EA15K03	cartridge​	3.56​	2.45​	1.37​	NA​	NA​	NA​	NA​
EA15K04	cartridge​	4.66​	2.75​	1.13​	NA​	NA​	NA​	NA​
EA15K09	spin-on​	2.90​	2.68​	3/4 - 16UNS​	2.47​	2.13​	11 to 17 PSI​	Yes​
EA15K10	spin-on​	2.90​	2.68​	3/4 - 16UNS​	2.47​	2.13​	11 to 17 PSI​	Yes​
EA15K12	spin-on​	2.46​	2.68​	M20 x 1.5​	2.47​	2.13​	11 to 17 PSI​	Yes​
EA15K13	spin-on​	3.35​	2.68​	M20 x 1.5​	2.47​	2.13​	11 to 17 PSI​	Yes​
EA15K20	spin-on​	3.08​	3.12​	M20 x 1.5​	2.45​	2.05​	11 to 17 PSI​	Yes​
EA15K29	spin-on​	3.40​	2.96​	M18 x 1.5​	2.76​	2.39​	No​	Yes​
EA15K32	spin-on​	3.40​	2.96​	13/16 - 16UNS​	2.76​	2.39​	No​	Yes​
EA15K50	spin-on​	3.40​	2.96​	M22 x 1.5​	2.76​	2.39​	11 to 17 PSI​	Yes​
EA15K51	spin-on​	3.40​	2.98​	3/4 - 16 UNS​	2.76​	2.39​	11 to 17 PSI​	Yes​
EA15K88	cartridge​	6.54​	3.34​	1.52​	NA​	NA​	NA​	NA​
EAO11	spin-on​	3.75​	3.65​	M22 x 1.5​	2.81​	2.42​	11 to 17 PSI​	Yes​
EAO15	spin-on​	5.37​	3.65​	3/4 - 16 UNF​	2.81​	2.42​	11 to 17 PSI​	Yes​
EAO17	spin-on​	4.45​	2.96​	M22 x 1.5​	2.76​	2.39​	11 to 17 PSI​	Yes​
EAO18	spin-on​	4.45​	2.96​	M22 x 1.5​	2.76​	2.39​	11 to 17 PSI​	Yes​
EAO23	spin-on​	4.75​	2.96​	M18 x 1.5​	2.76​	2.39​	No​	Yes​
EAO24	spin-on​	5.37​	3.67​	13/16 - 16UNS​	3.46​	3.08​	No​	Yes​
EAO26	spin-on​	6.77​	3.66​	3/4 - 16 UNF​	2.81​	2.42​	11 to 17 PSI​	Yes​
EAO34	spin-on​	4.75​	2.98​	3/4 - 16 UNS​	2.76​	2.39​	11 to 17 PSI​	Yes​
EAO37	spin-on​	4.75​	2.98​	3/4 - 16 UNS​	2.76​	2.39​	11 to 17 PSI​	Yes​
EAO38	spin-on​	3.87​	3.12​	3/4 - 16 UNS​	2.45​	2.13​	No​	Yes​
EAO42	spin-on​	3.75​	3.65​	3/4 - 16UNF​	2.81​	2.42​	11 to 17 PSI​	Yes​
EAO52	spin-on​	5.37​	3.69​	13/16 - 16UNS​	3.48​	3.08​	11 to 17 PSI​	Yes​
EAO59	spin-on​	3.08​	3.67​	13/16 - 16UNS​	3.46​	3.08​	No​	Yes​
EAO64	spin-on​	4.45​	2.96​	13/16 - 16UNS​	2.76​	2.39​	No​	Yes​
EAO80	spin-on​	6.87​	3.67​	1 - 16UNF​	2.81​	2.42​	No​	No​
EAO98	spin-on​	6.61​	3.67​	1 - 16UNF​	2.81​	2.42​	18 to 22 PSI​	Yes​
EAO99	spin-on​	7.98​	4.28​	1 1/2 - 16UN​	4.00​	3.63​	No​	No​