Mobil Clean 5000/GMC Denali 6.0/3,000miles

[GMBoy]

Background: I bought a new GMC Sierra Denali Crewcab with the 345hp 6.0L and did the first oil change at 1,800 miles and wanted to use a dyno oil first before going to Mobil 1 at around 5k miles. I am not impressed with Mobil 5000...especially when Blackstone recommends 3,100 mile intervals! I had much higher TBN with Mobil 1 in my Jeep 4.0 with nearly 7,000 miles on that oil sample. I did not expect Clean 5000 to match M1, but I would have hoped for a better showing than this. Perhaps it is not all the oil, but the newness of the engine.

What do the BITOG experts think?

Oil used: Mobil Clean 5000 5W/30
Miles on oil: 3,078 - no make up oil needed.

Blackstone comments: "You are able to see most anything come up high in the first or second oil sample from an engine, so there is nothing terribly startling about any of the data in this report. This type of oil uses sodium as an additive though, so we've put a "?" in the anti-freeze slot. That is because if there was a little anti-freeze in this oil we couldn't see it. Our ID for anti-freeze is sodium. Mobil 1 doesn't use it so we should be able to tell you more in your next Mobil 1 sample. Silicon and copper are high due to the newness of the engine. The TBN was 2.7, still okay. Stay at 3,100 miles use next sample.

Test results:

aluminum - 3
chromium - 0
iron - 18
copper - 138
lead - 5
tin - 0
moly - 109
nickel - 0
maganese - 3
silver - 0
titanium - 0
potassium - 2
boron - 28
silicon - 42
sodium - 223
calcium - 1566
magnesium - 9
phosporus - 568
zinc - 681
barium -0

Sus Viscosity @ 210degrees = 55.4
flashpoint = 390
fuel = antifreeze = ? due to oil used
water= 0
insolubles= 0.2

TBN = 2.7

 

[dave1251]

This is during your break in right. That will explan a lot is going on right now. A UOA will not be a very helpfull for the first 15,000 of your engine's life. But nice truck.

 

[HardbodyLoyalist]

Just make sure on your next UOA that those copper and silicon numbers come down.

 

[Triple_Se7en]

Too early for a UOA.

Invest after 15K or a few months prior to your warranty expiration -- whichever comes first.

 

[TooSlick]

How much oil life was left, according to the Oil Life Monitor?

I suspect both the Cu and Si is primarily chemical leaching from seal/gasket materials and will drop after you have 20,000 miles on this engine. A big V-8 engine with a 5-7 quart sump will deplete the oil more rapidly than a fuel efficiency, four banger. So what's you're seeing is completely normal.

I'd start with a 6k-7k run on the Mobil 1 (I'd use the more robust, EP version) and see how much reserve you have left.

TS

 

[GMBoy]

I agree with everyone about not doing UOA's until later on, but I just had to know. The oil change indicater, if I recall correctly. said I had 53% oil life left.

 

[dave1251]

When I had my silverado the OLM would go off around 7-9K. There is a 12K UOA with the 5.3 vortec on havoline convental on here that was just super.

 

[m2200b]

I think the miles UOA recommendation relates to the high metals rather than the TBN of M5000.

 

[Blue99]

quote:

---

There is a 12K UOA with the 5.3 vortec on havoline convental on here that was just super.

---

No, If you read all the posts in that UOA & the additional threads that it generated, the results were anything but super.

Bottom line is that the 5.3L engine was stressed by that overdue 12k OCI, and the results will show up in later UOA's.

The owner also stated that the truck was company supplied/leased & that he only checked the oil once or twice during the entire run.

- Can't imagine anyone doing that with a vehicle paid for out of their own pocket!

 

[addyguy]

With a TBN of 2.7, this oil would have made it to 'where it was supposed to' ie, 5000 miles. It did fine for the service....

 

[Winston]

TBN's do not drop linearly. It would have been fine at 5k. Blackstone is recommending changing at 3k because of the contaminants, not because of the oil TBN.

 

[Buffman]

It's interesting that the 5w30 MC5000 has the high sodium levels (from UOAs) but the 10w30 doesn't (based on my UOAs)