Tried it all, I need help. A constant Oil pressure fight.

[Collinmcballin]

Have you considered running 10-40 or 20-50 in your motor? If the tolerances have widened this may quiet down the motor a bit and give it a bit more buffer. I get that it calls for 5/30 from factory, but that was a trip to the moon ago and things are different inside that motor at this point...

Yep, I think on page 1 I mentioned I've been running 10-40 for a while... Seems to be the same results

 

[Collinmcballin]

Another update!
So far so good. Still hanging on a minimum of 38psi....nice!

For some reason; recently she dumps oil, baaaad. Replaced cam sensor and crank sensor o-rings a month ago... Got worse since... It's just dumping oil out/up/around bellhousing, starter, oil filter and sheeeeesh.... Everywhere.
The underside of my truck is absolutely spackled, exhaust, trans, even my Thule bike rack is polka dotted. Freaking mess
What can even cause it to leak this bad? Anytime heat/ac is on it smells like my 97 cr250 2 stoke... LOL
I'm tempted to yank the motor now. It's so annoying. throw cam bearings in like ya'll mentioned, and be done with this thing already.

 

[OR VietVet]

Oil pressure sensor puking or back of intake puking? Check the oil filter adaptor too.

 

[AngryFish]

What can even cause it to leak this bad?

Well, the good news is that you'll find it if you pull the motor, so you may want to get parts ready. if you know the valley plate and intake and such are good, it's very probably the same issue I just had repaired at just shy of 300k.

On the back of the engine block, there is a cover that holds the rear main seal. The top of this cover also has an oil gallery that moves oil from the left to the right side of the block (for the heads, I think...). The cover has a rubbery elastomer seal that likes to go bad and cook, and when that fails it will spray oil. And it coats everything underneath... I had that issue for sure and thought my rear diff was leaking again at first. Usually cooks after about 150,000 miles, and it's on borrowed time after that causing a minor coating of oil that looks like it's from the oil filter adapter but isn't.

So good news, it's not the rear main. The bad news is that it might as well be.

Another option is leaks from the valley cover plate being loose, so you can check that, but probably not a common issue. It was loose on my truck, but I also was puking oil from the rear main cover plate. The valley plate was a gentle seep by comparison.

 

[AngryFish]

For reference, the rear cover is part #28 and the seal in question is #29. Rear main seal itself is #27. Usually available from GM as a kit with 27, 28, and 29. I don't have a number though...

 

[Collinmcballin]

Just checking in here again. Engine is still leaking worse than ever. Qt a week. Under the truck is soaked. Still runs like a champ of course. My pops talked with a few guys when he was picking up an engine last weekend. They said the motor is tired and ready for a new one. Ehh...
Oil pressure has still been spectacular for a FEW months now. It just doesn't like off roading it seems. Next plan is to install that oil cooler right behind the removable bumper valance air ducts.
Also starting an engine swap on my mom's Yukon this weekend.
Seems as my oil pressure dilemma is still hibernating...