0-20w oil

[StephenPT]

My theory is that the engine oil peak operating temp of the LM2 is in a range that the kinematic viscosity is thin enough that it slips by rings, turbocharger seals, etc. At 0W-20, the oil is already "thin" and when you run the oil at 220F+ unloaded and towing 240F+ temps you're more likely to use oil. It takes the engine ~45min to start seeing the 220F+ oil temps, so if you're not driving on extended road trips you won't see any consumption based on driving unloaded. Towing oil temps rise quickly, but usually towing is limited to a few hundred miles here and there and not a daily occurrence.

It's interesting though that Georgia 4Low saw oil consumption using AC Delco 0W-20 but isn't seeing it with the same weight (different brand). Perhaps the Mobil ESP 0W-20 formulation reacts differently to the higher oil temps? It's certainly worth a try on my end to make the switch as the oil is still Dexos-D rated and I don't have to worry about voiding the warranty...

 

[15burban]

The mobil 0w20 could possibly be a "heavier" 20 weight. A guy would have to lookup the specs of it compared to the ac delco. Just like the ac delco could be on the thinner side of a 20 weight. I'm not saying they are but it's a possibility.

 

[Stbentoak]

My theory is that the engine oil peak operating temp of the LM2 is in a range that the kinematic viscosity is thin enough that it slips by rings, turbocharger seals, etc. At 0W-20, the oil is already "thin" and when you run the oil at 220F+ unloaded and towing 240F+ temps you're more likely to use oil. It takes the engine ~45min to start seeing the 220F+ oil temps, so if you're not driving on extended road trips you won't see any consumption based on driving unloaded. Towing oil temps rise quickly, but usually towing is limited to a few hundred miles here and there and not a daily occurrence.

It's interesting though that Georgia 4Low saw oil consumption using AC Delco 0W-20 but isn't seeing it with the same weight (different brand). Perhaps the Mobil ESP 0W-20 formulation reacts differently to the higher oil temps? It's certainly worth a try on my end to make the switch as the oil is still Dexos-D rated and I don't have to worry about voiding the warranty...

As an opinion, I believe they are the exact same oil, bottled on the same line, and the only difference is the green dye they put in the Mobil to differentiate. Why would they want to mess with the formulation? Both work and both conform, and both come from the same big tank at the Mobil factory....

 

[StephenPT]

As an opinion, I believe they are the exact same oil, bottled on the same line, and the only difference is the green dye they put in the Mobil to differentiate. Why would they want to mess with the formulation? Both work and both conform, and both come from the same big tank at the Mobil factory....

I believe your opinion is indeed fact.

Since I made that post I did some more research - I looked up the MSDS for the AC Delco oil - guess who the manufacturer is....

ExxonMobil