Took The Oil Pan Off Again

[donjetman]

As you may recall? in June of 2024 I had the pan off of my 198k miles (at the time) 2007 6.2L L92 to see how well my MIX of 2 qts of Valvoline Premium Blue "Restore" 10w-30, and 4 qts of Mobil 1 Euro 0w-40 were cleaning the insides of the engine. After only 2500 miles it was impressive. Now the engine has 200,500 miles and the same oil & filter have 5000 miles, so it is time for a change and another look see..

So, last week I removed the oil pan again (I have my own lift) to see how well my oil mix is cleaning the inside of the engine. VPB Restore oil was/is designed to clean. Don't confuse VPB "Restore" with their newish offering "Restore and Protect". They are completely different animals. "Restore" is much more aggressive/effective. In 2024 I saved and reinstalled the oil & filter (Fram Ultra XG10060) that came out/off.

As you can see in the pics here, there's a lot LESS crud in the bottom of the pan this time compared to 6 of 24. Both the 6/24 pics and these 2025 pics are after 2500 miles.

OLM said 47% remaining
First pic is from last week, 2nd pic = last summer

Waiting on the used oil analysis report to arrive.
I put a fresh 50/50 mix of these two oils back in and a Purolator Boss PBL22500 filter. I'll drop the pan again in 5000 miles for another look see.
Here's the June 2024 thread: https://www.tahoeyukonforum.com/threads/valley-cover-crank-pulley-etc.149036/#post-1885986

 

[j91z28d1]

I'm guessing you dropped the pan took and pic and didn't clean it while off?

that's commitment to the experiment

 

[donjetman]

This is the third time I've had it off since purchasing the vehicle in 2018.
Pan is always cleaned out thoughly before it goes back on.
Like:

 

[j91z28d1]

ahh. OK. I saw crud in the same spots just less of it.

not that it would have been anything wrong if you did, just not sure I could.

this engine was pretty gunked up huh seems to be cleaning up nicely thou.

 

[strutaeng]

Looks pretty good!

The oil pan on my 06 Suburban LQ4 looked kinda like the crunchy photo, only a bit crunchier slightly. My truck had around 225k then and the oil pan had apparently never been off (still had those rivets.)

 

[Charlie207]

Looks pretty good!

The oil pan on my 06 Suburban LQ4 looked kinda like the crunchy photo, only a bit crunchier slightly. My truck had around 225k then and the oil pan had apparently never been off (still had those rivets.)

Yeah, the pan on the 2008 155,*** mile LY6 I rebuilt had never been off, or had the oil changed (hyperbole, but yeah), and the oil pan had a solid 1/2" of schmoo on the bottom.

It was amazing that I lyvthe cam bearings were damaged, and the mains & con-rods bears were still great. (Per my machinist)

I started out the first fill-up of the LY6 with VR&P about 11000 miles ago, but am going to alternate with whatever the cheapest full-synthetic is every other 5000 mile oil change.

 

[donjetman]

I started out the first fill-up of the LY6 with VR&P about 11000 miles ago, but am going to alternate with whatever the cheapest full-synthetic is every other 5000 mile oil change.

I've found that VRP is NOT nearly as effective as VPB"Restore". I have another vehicle I've tested VRP on.

 

[alvocado]

Thanks for posting details on this as it's helpful to see actual results. I'd be willing to run the VRP Restore but wouldn't drop the pan; I'd have to drain only. I did my pan twice in a week earlier this summer before realizing a leak was from the rear main seal so dropping the pan anytime soon with the truck on jack stands is not in the cards.

 

[donjetman]

yeah, my lift (and being retired) was a game changer.
I can have the pan off in 2 hrs and back on again in 3. And I reuse the gasket.

 

[Charlie207]

I've found that VRP is NOT nearly as effective as VPB"Restore". I have another vehicle I've tested VRP on.

Yeah, luckily this LY6 started out clean as a whistle when I swapped it in.

 

[donjetman]

AND
I wouldn't run VRP longer that about 3k miles in our not so good mpg TYE.
VRP doesn't have much staying power (group 4 oils).

 

[alpha_omega]

I’ll be curious to see what the report says. Who did you go with this time?

What do you mean by this?

AND
I wouldn't run VRP longer that about 3k miles in our not so good mpg TYE.
VRP doesn't have much staying power (group 4 oils).

Edit: What do you have in the drain plug hole? Is that your clean out bolt?

 

[donjetman]

I’ll be curious to see what the report says. Who did you go with this time?

What do you mean by this?



Edit: What do you have in the drain plug hole? Is that your clean out bolt?

Here's the virgin unused report for VRP. Starts with a low base# that depletes rapidly, and oxidation indicates no group4 base oil (ester, etc).

My other vehicle is easy on oil. A 5k mile oci is all VRP can go in it.

Drain plug is in the drain hole.

 

[Joseph Garcia]

Here's the virgin unused report for VRP. Starts with a low base# that depletes rapidly, and oxidation indicates no group4 base oil (ester, etc).

View attachment 465219

My other vehicle is easy on oil. A 5k mile oci is all VRP can go in it.

Drain plug is in the drain hole.

If you have physically removed the AFM parts and disabled the software, you can delete the oil bypass device in the oil pan, and replace it with a threaded plug. There is a kit available for this.

You will get super oil pressure after this delete, if you are interested.

 

[donjetman]

@Joseph Garcia
My engine is an L92 and never had any afm hardware
but
in 2018, I did TSB 10-06-01-008M which states the shield is to be installed even on the L92, so I did
Went from oil consumption (stuck piston rings) of 1 to 2 oz per 100 miles, too no consumption. And its still nothing @ 200+k miles, 70k miles 7 yrs later

 

[Scrappycrow]

Am I reading the TSB correctly that engines built after October 2010 already have the AFM valve shield in place?

 

[rdezs]

Am I reading the TSB correctly that engines built after October 2010 already have the AFM valve shield in place?

Yes, I believe that is correct. Our 2014 had one on from the factory, as well as a 2010 and a 2012 I did AFM deletes on.

Not sure why an L92 would have it, other than perhaps having some consistency in engine blocks in manufacturing. The purpose of that pressure relief is to protect the solenoids in the AFM VLOM, which can get damaged at something over 60 PSI.

The last AFM I did on an L94, involved installing an L92 OEM camshaft, and a Melling 10296 oil pump with the +10 psi spring that comes installed with it. Threaded stainless steel bolt to block off that relief valve in the oil pan. Plug the towers with steel plugs tapped into them. Cold start, 68 PSI idol. Hot idle 26 PSI. Fully warmed up running down the freeway at 1700 RPM, 47 PSI. And that number goes up with corresponding RPM from there, to about 60 PSI at 4,000 RPM.

On the AFM deletes I've done on L94s, using the same components in all, those figures fluctuate +/-3 PSI, which is probably due to variances in crankshaft/camshaft bearing wear, and lifter bore wear. All were checked out using 5W30 Valvoline full synthetic, with the OEM ACDelco filter.

Highway fuel mileage on all of them increased between one and three miles per gallon, what's really raises the question on if the AFM system actually saved any fuel at all.

 

[Joseph Garcia]

@Joseph Garcia
My engine is an L92 and never had any afm hardware
but
in 2018, I did TSB 10-06-01-008M which states the shield is to be installed even on the L92, so I did
Went from oil consumption (stuck piston rings) of 1 to 2 oz per 100 miles, too no consumption. And its still nothing @ 200+k miles, 70k miles 7 yrs later

Mine is an L92, as well, but my oil pan (not original) still had the pressure relief valve in it. Apparently, GM did not (or does not now) have more than 1 oil pan configuration.

The deflector is a good add-on, if you don't delete the valve in its entirety.

 

[Marky Dissod]

Highway fuel mileage on all of them increased between 1 - 3MpG,
which really raises the question on if AFM actually saved any fuel at all.

TLDR: yes V4 mode saved fuel, it's just that the vast majority of the fuel saved was when the engine/vehicle was brand new.

The more one learns about how vehicles are driven during the CAFE MpG test scoring,
the more one'll understand that Engine Half@$$ & Cylinder Confusion show best results SPECIFICALLY DURING CAFE MpG testing when vehicles are brand new,
and that as the engine gets older the MpG savings wane even if the owner operator changes their oil 2x as often as the OLM indicates.

A.S.S., Engine Half@$$ / Cylinder Confusion, & 0W20 (as well as even thinner oils) all have one thing in common:
their existence is chiefly justified by CAFE MpG test drive cycles, which do not realistically simulate how normal people drive (in fact they never have and never will).

 

[j91z28d1]

I believe the drive cycle is much slower highway speeds than is normally driven these days and steady throttle inputs. where most people drive 75 mph these days with constant throttle foot. both basically keep a normal driver out of 4cyl mode while pushing a brick thru the air at 75mph haha.


oddly in most cars, I usually get a few mpg better on the hyway then the epa rating. especially manual cars. this truck, nope haha.