Oil leak from Oil Pan and Oil Pressure Relief Valve

[05gto]

I'm having an issue where oil is leaking badly from oil pan during load. Have a 6.2L 2012 yukon that has been rebuilt with dod/afm delete as well as vvt delete. Bought Part# 12710304 Oil Pump directly from GM. Getting close to 70 psi oil pressure idle on cold start. Around 40 when warm. Under load of drive it leaks and drops to around 22 psi. My thought is pressure is too high causing the leak (video link below showing leak) . Oil pan gasket has been replaced twice, and oil pan replaced once.

***Question: will putting a oil pressure in oil valve back in oil pan help relieve pressure, or is this valve only activated by dod/afm? Will I have to buy a smaller oil pump?

 

[2017sltXL]

You are positive this leak is not coming from above the pan? That is an insane leak for a pan gasket. The pan gasket itself is not under pressure besides the oil filter/cooler fittings or block off plate. I'm curious why the starter is so oily since it's above the pan, but that could be due to windage when it's going down the road.
I think that pump is actually meant for an AFM engine, but I still can't imagine it would be the main issue.
Any chance it's coming from something else further up like the oil pressure switch or the valley cover?

 

[Fless]

I was also thinking it could be something higher, or even toward the front of the block, based on where the oil is first being blown backward.

 

[05gto]

You are positive this leak is not coming from above the pan? That is an insane leak for a pan gasket. The pan gasket itself is not under pressure besides the oil filter/cooler fittings or block off plate. I'm curious why the starter is so oily since it's above the pan, but that could be due to windage when it's going down the road.
I think that pump is actually meant for an AFM engine, but I still can't imagine it would be the main issue.
Any chance it's coming from something else further up like the oil pressure switch or the valley cover?

That was my thoughts as well with valley cover. Changed it and the gasket. Changed valve cover gaskets as well.

It's been a gremlin. Doesn't leak even after rpms a raised. Only after engine load in drive.

 

[05gto]

I was also thinking it could be something higher, or even toward the front of the block, based on where the oil is first being blown backward.

Definitely not front. Dry as a desert. Flywheel is dry as well because at first I thought it might be rear main seal or rear plate, but that area seems dry as well under Trans bell housing.

 

[lspann3525]

I'm having an issue where oil is leaking badly from oil pan during load. Have a 6.2L 2012 yukon that has been rebuilt with dod/afm delete as well as vvt delete. Bought Part# 12710304 Oil Pump directly from GM. Getting close to 70 psi oil pressure idle on cold start. Around 40 when warm. Under load of drive it leaks and drops to around 22 psi. My thought is pressure is too high causing the leak (video link below showing leak) . Oil pan gasket has been replaced twice, and oil pan replaced once.

***Question: will putting a oil pressure in oil valve back in oil pan help relieve pressure, or is this valve only activated by dod/afm? Will I have to buy a smaller oil pump?

Is the oil pressure valve in the oil pan plugged?

The Oil pump you ordered is an AFM Oil pump is pretty much just a high pressure oil pump. May want to try a STD Volume Meiling oil pump. Thats what Im running on my rebuild.

 

[2017sltXL]

That was my thoughts as well with valley cover. Changed it and the gasket. Changed valve cover gaskets as well.

It's been a gremlin. Doesn't leak even after rpms a raised. Only after engine load in drive.

Only leaks under load, so the engine has to flex a little bit.
Any chance it's an oil cooler line leak that moves just enough when the engine moves under load?
I see your cooling fan runs in this video, so it's possible it's migrating a bit.

 

[Foggy]

I don't see how any factory oil pump would ever put out enough pressure
to cause a leak somewhere.
I think you've just got an old fashioned oil leak.
Check cooler lines as mentioned

 

[05gto]

Is the oil pressure valve in the oil pan plugged?

The Oil pump you ordered is an AFM Oil pump is pretty much just a high pressure oil pump. May want to try a STD Volume Meiling oil pump. Thats what Im running on my rebuild.

Yes, I plugged it. Wondering if I should put the relief valve back. I've heard that only helps with afm, so I'm not sure

 

[SpareParts]

Looks like it is coming from the front passenger side of the engine. I don't see how oil psi could be the problem in that area.
I know you said the gasket was replaced, but the only thing i can think of is a misplaced gasket with a big gap between the pan and block.
Crank sensor? Maybe that plug in the block above the starter but not sure if that's oil or water.

 

[2017sltXL]

Crank position sensor?
Oops, I see Spare Parts just mentioned that in the last post.
Might be time to think about some UV dye to chase it down. Only so many leak points it could be.

 

[05gto]

Looks like it is coming from the front passenger side of the engine. I don't see how oil psi could be the problem in that area.
I know you said the gasket was replaced, but the only thing i can think of is a misplaced gasket with a big gap between the pan and block.
Crank sensor? Maybe that plug in the block above the starter but not sure if that's oil or water.

It's really only from about 4 inches of the front and back and both sides that it's leaking. Though more from the passenger side than driver. When I get a chance to check again I'm going to see if the rear plate is lined up correctly. Wondering if it's possible that the plate is hanging lower than it's supposed to be and forcing it to create a gap on sides. Not certain but it makes sense to me why it's not really leaking from back and front part of pan. If that's not possible I'm at a loss

 

[j91z28d1]

that's the craziest thing I've seen.

have you had the front and back cover off the engine? there's alignment tools for those so the pan has a flat surface to seal too.

what brand oil pan gasket did you use? not rust it matters, just curious.

 

[2017sltXL]

Probably a stupid question, but you dabbed some RTV in all four corners before assembly? And didn't smear it anywhere else?
Double check torque specs...
Pan is straight with the back of the block and not protruding past, but if you didn't have the trans out then I can't see how that would be an issue.
Also, if you didn't do the rear main then that plate should not have moved at all.
Also can't be forward really much at all, I think the spec is .010" max IIRC.

 

[05gto]

Probably a stupid question, but you dabbed some RTV in all four corners before assembly? And didn't smear it anywhere else?
Double check torque specs...
Pan is straight with the back of the block and not protruding past, but if you didn't have the trans out then I can't see how that would be an issue.
Also, if you didn't do the rear main then that plate should not have moved at all.
Also can't be forward really much at all, I think the spec is .010" max IIRC.

It's been a complete rebuild. Have replaced pretty much everything. And yes, I did use RTV on the corners only.

 

[05gto]

that's the craziest thing I've seen.

have you had the front and back cover off the engine? there's alignment tools for those so the pan has a flat surface to seal too.

what brand oil pan gasket did you use? not rust it matters, just curious.

Did it with stock pan, accidently broke a bolt on oil cooler like that then subsequently broke an extractor. I then replaced with a Dorman

 

[j91z28d1]

if the whole thing as been apart. could it be leaking from the little 10mm side bolts that go into the main caps?

 

[rdezs]

Sometimes you have to step back and think outside the box. Your oil pan gasket is fine. When you did the AFM delete, you had to remove the dipstick on the passenger side to deal with the exhaust manifold. To me, based on where the oils dropping down, it looks like the dipstick is not seated all the way in the block. (And if it has another half inch to go, the crankcase is quite overfilled)

I've seen cases where people have completely missed the dipstick tube opening in the block when trying to reinstall it. Also if the o-ring on the tube is completely trashed. And then there's been several cases where the lower part of the dipstick tube is completely rusted through.

Based on the amount of pressure pushing oil out, it's quite possible it's aggravated by a plugged PCV system. Verify you have vacuum in the crankcase at idle. (At idle, if you just lift the dipstick up your idle should change a little, due to the vacuum leak you just created.) You can easily adapt a hose to fit a common vacuum gauge and connect it on the passenger side valve cover which is the fresh air intake. After about 10 seconds you should start to see a slow increase in vacuum. If the PCV system is plugged or even partially plugged, that will pressurize your crankcase and the pressure will blow out the weakest seal. (I replace that o-ring on the dipstick anytime I have it out)

Well that's my two cents worth..... I could be wrong, but I don't think so

 

[rdezs]

Note.... The same theory applies to the camshaft position sensor.... If the o-ring got cut during installation, and aggravated by a partially or fully plugged PCV system.

 

[Geotrash]

Does the problem also occur when the engine is warmed up and the oil pressure has tapered down a bit with the warmer oil?

The oil pressure relief valve in the pan is a pop-off valve. It's spring loaded and is supposed to pop open when the AFM system changes modes with the pressure spikes, and then pops back closed. If you removed it and the AFM system, there really is no reason for it. Your oil pump pressure spring is what governs the output pressure from the pump. Melling HP pumps ship with 3 different springs so you can choose a lower pressure spring if you want to. But that said, I see no problem with the oil pressures you mentioned. My 2012 has a Melling high pressure oil pump in it using the spring that shipped installed in it, and I see similar pressures to yours across the range. Mine still has the pop-off valve in the oil pan, but I doubt it's even opening because there are no pressure spikes from the AFM system any more since I deleted the whole thing. I did replace that pop-off valve with a new one, but I still don't see any issues with your pressures.

So, my money is on the crank position sensor o-ring above/behind the starter. And as rdezs says, it's being aggravated by a plugged PCV system.

The only other thing I can think of that hasn't been mentioned yet is that the 6.2L blocks have occasionally had porous casting issues. When that happens, oil can leak right through the aluminum. But I've only read of it in articles, and have never seen anyone here having that problem.