Mobil 1 EP 5w-30 @ 13k mi; GM 5.3L 238k mi

Originally Posted by LeakySeals
I could have missed this. Sorry if already discussed. A 2008 5.3 has AFM. That system is prone to malfunction, the lifters wear themselves out grinding on the cam lobes. There can also be low oil pressure issues due to another common problem, the oil pickup tube oring fails. Oil flow is an issue with these engines. I would not use any type of filtration that restricts flow. The updated valve cover will hopefully help with oil consumption through cyl #7. But sometimes it's too late, rings are stuck and a soak helps


I have the AFM disabled in the custom tune. I replaced the oil pump and O-ring with a HV/HP oil pump a while ago. I added all the aftermarket filtration in order to try and lower the oil pressure a bit as the ECM didn't like "seeing" the higher pressure. It's all covered in an earlier post.
 
Originally Posted by Kbuskill
Originally Posted by LeakySeals
I could have missed this. Sorry if already discussed. A 2008 5.3 has AFM. That system is prone to malfunction, the lifters wear themselves out grinding on the cam lobes. There can also be low oil pressure issues due to another common problem, the oil pickup tube oring fails. Oil flow is an issue with these engines. I would not use any type of filtration that restricts flow. The updated valve cover will hopefully help with oil consumption through cyl #7. But sometimes it's too late, rings are stuck and a soak helps


I have the AFM disabled in the custom tune. I replaced the oil pump and O-ring with a HV/HP oil pump a while ago. I added all the aftermarket filtration in order to try and lower the oil pressure a bit as the ECM didn't like "seeing" the higher pressure. It's all covered in an earlier post.

Got it. I've used the melling high-volume pump and didn't have any problems. I don't think ls engines like the high pressure pumps but I'm not positive about that . Also you mentioned disabling AFM with a tune. So that means the AFM lifters are still in there. And can still be a problem if AFM is on or off. I suspect that may be a contributor to the wear metals in the sample.
 
All the high volume pumps do is rob power. I've run a 5.3L to 7500 rpm on a stock pump with no pressure drop. I just don't see the need unless you're really pushing the engine.

Remember that higher oil pressure also increases the risk of aeration as it increases the capacity for entrained air. I aim for ~20 psi at hot idle and increasing 10 psi per 1k rpm. You only need sufficient pressure to ensure the oil wedge in the bearings are filled each rotation while also getting flow to the top of the engine. This doesn't take much pressure at all, especially at idle. Just 6-8 psi is all that's actually needed. You want pressure to increase with rpm because that window to fill the oil wedge gets shorter and shorter with more rpm.

Pretty much, by the time I reach a point that a high volume pump is actually necessary, I'm ready to go dry sump anyway. The only application I'd use an HV pump is if the particular racing class requires a wet sump.
 
JMO a high pressure oil pump is a band aid for a problem. A high volume pump is more beneficial but the high pressure part is just a band aid and has the potential to cause more problems than fix anything.
 
Originally Posted by LeakySeals
Originally Posted by Kbuskill
Originally Posted by LeakySeals
I could have missed this. Sorry if already discussed. A 2008 5.3 has AFM. That system is prone to malfunction, the lifters wear themselves out grinding on the cam lobes. There can also be low oil pressure issues due to another common problem, the oil pickup tube oring fails. Oil flow is an issue with these engines. I would not use any type of filtration that restricts flow. The updated valve cover will hopefully help with oil consumption through cyl #7. But sometimes it's too late, rings are stuck and a soak helps


I have the AFM disabled in the custom tune. I replaced the oil pump and O-ring with a HV/HP oil pump a while ago. I added all the aftermarket filtration in order to try and lower the oil pressure a bit as the ECM didn't like "seeing" the higher pressure. It's all covered in an earlier post.

Got it. I've used the melling high-volume pump and didn't have any problems. I don't think ls engines like the high pressure pumps but I'm not positive about that . Also you mentioned disabling AFM with a tune. So that means the AFM lifters are still in there. And can still be a problem if AFM is on or off. I suspect that may be a contributor to the wear metals in the sample.


You are correct, the AFM hardware is still intact and could be a potential problem down the road. I tuned it out so atleast the lifters aren't locking and unlocking all the time, which in my opinion, would increase the likelihood of them having an issue.
 
Originally Posted by RDY4WAR
All the high volume pumps do is rob power. I've run a 5.3L to 7500 rpm on a stock pump with no pressure drop. I just don't see the need unless you're really pushing the engine.

Remember that higher oil pressure also increases the risk of aeration as it increases the capacity for entrained air. I aim for ~20 psi at hot idle and increasing 10 psi per 1k rpm. You only need sufficient pressure to ensure the oil wedge in the bearings are filled each rotation while also getting flow to the top of the engine. This doesn't take much pressure at all, especially at idle. Just 6-8 psi is all that's actually needed. You want pressure to increase with rpm because that window to fill the oil wedge gets shorter and shorter with more rpm.

Pretty much, by the time I reach a point that a high volume pump is actually necessary, I'm ready to go dry sump anyway. The only application I'd use an HV pump is if the particular racing class requires a wet sump.


The AFM engines actually come from the factory with a HV pump.
 
Originally Posted by mattd
JMO a high pressure oil pump is a band aid for a problem. A high volume pump is more beneficial but the high pressure part is just a band aid and has the potential to cause more problems than fix anything.


I replaced the oil pump at the same time as the timing chain as preventative maintenance. GM claims the timing chain is good for 200k miles from what I have read.

I decided to go with the HV/HP pump because the LMG 5.3L (AFM) came with a HV pump AND I figured with almost 200k miles on it at the time that a little added pressure wouldn't hurt. It's only supposed to be 10% more pressure.
 
I supervised while my oldest son swapped the driverside valve cover out for the new revised valve cover that relocates the inlet hole for the PCV system.

I wanted to paint both valve covers with the red wrinkle paint by VHT but none of my local parts houses carry it in stock so I just had him install it as is.


This is a comparison shot of the older style valve cover on the bottom and the new revised valve cover on the top.
rps20200118_193255_384.jpg

This is just a pic of what the top of the head looks like. rps20200118_193320_066.jpg

Pretty dang clean for having almost 250k miles on the ol' girl and running 13k-15k mile OCIs, if I do say so myself.

rps20200118_193255_384.jpg


rps20200118_193320_066.jpg
 
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Ken, your right, CLEAN ! Good job.

I think you should plumb you oil cooler to the oil cooler pad/circuit on the block, and not the oil filter circuit.

If I did any towing I would definitely add a trans and oil cooler to my 07 Yukon 6.2 and 6L80.

Like you, I prefer to do xOCIs , and sump capacity is key. My aluminum block L92 is harder on oil than a cast iron equivalent. So, I hope to add a 1 gal external oil tank like the Viair tank pictured. It will easily fit on the driver side at the empty battery tray area horizonally or vertically. I may need to add and/or change fitting location(s). Here's a Viair LINK
Can be purchased on amazon for $49.
[Linked Image]
 
Can you elaborate more on adding this tank into your oil system or perhaps provide a link so I can read more about it?

Seems like it would be hard to get the oil out during an oil change or would you just not change "all" the oil?

Also seems like adding this above the level of the oil pan would cause the oil in the tank to try to fill the pan.

I would like to know more.
 
Have/weld a bung for a drain petcock at the tank low point, and have/add a bung/large pipe plug/fill cap at the high point. Have the inlet line and outlet line fittings on top of the tank. It can't/won't gravity feed down into the engine, for the same reason it doesn't from my bypass filter or your dual remote setup. Think about it.

I run in race car circles and a lot of my friends can weld, so this isn't that difficult. I build my own lines and can buy all the materials online or at the local speed shop.

I can hook it up in series with my existing bypass filter setup and an oil cooler.
 
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I see. Having the inlet and outlet on the top makes sense. I was thinking you were talking about hooking it to the existing ports on that tank which didn't make sense to me.
 
Latest oil sample after putting an additional 3k miles on this oil per Blackstone's recommendation.

rps20200213_214729_268.jpg
 
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Ken, like Blackstone said the lead is worrisome. But other than that it looked good.

Many experts recommend an oil change when TBN is 2/3s depleted from virgin. Assuming your oil started with a TBN of about 10, 3 is a good time to change it.

I like to change mine when TBN is between 2 and 3. For my 07 Denali w/L92 6.2, that's at about 8000 miles. My sump capacity is 6.5 qts.
 
Latest UOA after running the Mobil 1 5w30 EP and the dual Fram Ultraguard filters...

rps20210104_202155_711.jpg


Also decided I wanted to try a little thicker oil but Mobil doesn't make an EP oil in a 40 weight so I chose their Delvac Extreme 15w40 for this oil change along with the Fram Ultraguard filters again.

I did a VOA on the Delvac Extreme just to see where it started out at...

rps20210104_202502_245.jpg
 
At this point you've spent $500-$1000 solving a problem that may likely not exist. Ironically, it's quite likely you've damaged the vehicle.

This whole thing seems like an exercise in futility.
Like a solution in search of a problem.
Hundreds of dollars in aftermarket equipment.
Custom tunes, HV/HP pumps, bypass filtration systems, blah, blah, blah.
Hundreds of dollars on oil analyses.
15w-40 oil because, hey, why not?!?
All to arrive at prolonged excessively high lead numbers.

Here's a crazy idea, strip all that carp off. Run the engine bone stock. Run the OEM spec'd viscosity grade.
Do 3-4 oil/filter changes over 20k miles.
Then do a UOA.
In other words, establish a baseline of performance for this vehicle.
 
At this point you've spent $500-$1000 solving a problem that may likely not exist. Ironically, it's quite likely you've damaged the vehicle.

This whole thing seems like an exercise in futility.
Like a solution in search of a problem.
Hundreds of dollars in aftermarket equipment.
Custom tunes, HV/HP pumps, bypass filtration systems, blah, blah, blah.
Hundreds of dollars on oil analyses.
15w-40 oil because, hey, why not?!?
All to arrive at prolonged excessively high lead numbers.

Here's a crazy idea, strip all that carp off. Run the engine bone stock. Run the OEM spec'd viscosity grade.
Do 3-4 oil/filter changes over 20k miles.
Then do a UOA.
In other words, establish a baseline of performance for this vehicle.

It is an exercise in futility, as is everything else in life, you can't take any of it with you when you die, thanks for noticing.

I guess I, mistakenly, thought that others on here might just enjoy seeing data from other people's vehicles and the different setups they choose to run.

For the record I don't have a bypass filtration setup on this vehicle, just a dual remote mount filter setup.

I wasn't asking for advice on what I should or shouldn't do, just posting information for those who might care.

You are correct though, I should have done a baseline UOA before changing anything just to see what was what, but I didn't and I'm not going to the trouble to change everything back over so this is strictly for informational purposes for anyone who may find it interesting or amusing.
 
It is an exercise in futility, as is everything else in life, you can't take any of it with you when you die, thanks for noticing.

I guess I, mistakenly, thought that others on here might just enjoy seeing data from other people's vehicles and the different setups they choose to run.

For the record I don't have a bypass filtration setup on this vehicle, just a dual remote mount filter setup.

I wasn't asking for advice on what I should or shouldn't do, just posting information for those who might care.

You are correct though, I should have done a baseline UOA before changing anything just to see what was what, but I didn't and I'm not going to the trouble to change everything back over so this is strictly for informational purposes for anyone who may find it interesting or amusing.
It's not that others here don't enjoy seeing data. That's just your own speculation.

When a member posts something as you've done here, I would think you'd be looking for a response.
I highlighted the fact that you don't have a baseline to substantiate most of the things you've presented. And it appears that what has been done is quite possibly to the detriment of the vehicle.
If your motivation for doing so is because you enjoy wrenching, well then have at it. I hope you enjoy yourself.
If your motivation is to preserve or extend the life of the vehicle, then your information shows that your efforts may likely be misguided. And expensive. And possibly detrimental.

If that feedback is hard to swallow then accept my apologies. The intent is for all members here to learn from each other's experiences.

Cheers!
 
Imp4,
You could have presented your thoughts in a more friendly manner.

I agree that having a baseline without modifications would be useful, but shouting him down doesn't do anyone any service. There is something of a baseline with the 10/15/2018 UOA.

The tune to disable the AFM is normal and very widely run in the GM community, I would not ding him on that.

As he and others mentioned, the stock AFM pump is HV.

I don't think 15w40 is so bad, lots of people run Xw40 in their performance oriented LS motors and GM has moved to recommending it in Corvette, which is the same basic engine architecture. The difference between 0w40 and 15w40 is pretty nominal 9-10 months of the year in Florida.

anyway...rant on....
 
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