Here's a GM Technical Service Bulletin explaining why you should use 0W20 grade oil in the new truck engines. Don't listen to anyone on here that is telling you to go to a thicker grade engine oil. GM likes to run thin oils in their engines in the trucks due to the direct injection technology and for fuel economy purposes.
GM Engineers have put together this service bulletin that I pulled off GM Global.
#13-00-90-001: Information for Engine Oils Used in 2014 Model Year Vehicles - (Jun 27, 2013)
Subject: Information for Engine Oils Used in 2014 Model Year Vehicles
Models: 2014 GM Passenger Cars and Trucks
Only those oils displaying the dexos1™ trademark and a registered trademark logo on the front label of the container meet the demanding performance requirements and stringent quality standards set forth in the dexos1™ specification.
Look on the front label for either of the registered trademark logos shown above and the 11 digit alphanumeric dexos® license number on the back label to identify an authorized, licensed dexos1™ engine oil. Unless an oil package displays these two markings, the engine oil is not an authentic, licensed dexos® product and is not recommended for use in GM vehicles.
dexos1™ Engine Oil Specification
The dexos1™ specification was uniquely designed to complement the exacting requirements of GM's advanced engine technology. The specification has gone through an extensive developmental and testing process. It requires a number of proprietary tests that are not included in current industry standards and sets performance criteria at a level that exceeds many current standards. The result is a high performance fluid providing significant wear protection, improved piston cleanliness, a reduction in volatility and oil consumption, enhanced aeration control for improved fuel efficiency, and better oxidation properties.
The reasons for the new dexos1™ engine oil specification are as follows:
To meet environmental goals such as increasing fuel efficiency and reducing engine emissions.
To promote long engine life.
To minimize the number of engine oil changes in order to help meet the goal of lessening the industry's overall dependence on crude oil.
dexos1™ is a GM-developed engine oil specification that has been designed to provide the following benefits:
Further improve fuel economy, to meet future corporate average fuel economy (CAFE) requirements and fuel economy retention by allowing the oil to maintain its fuel economy benefits throughout the life of the oil.
More robust formulations for added engine protection and aeration performance.
Support the GM Oil Life System, thereby minimizing the replacement of engine oil, before its life has been depleted.
Reduce the duplication of requirements for a large number of internal GM engine oil specifications.
Frequently Asked Questions About dexos1™ 0W20 Engine Oil
Question: Why dexos1™ 0W20 engine oil?
Answer: The new 5.3L and 6.2L V8 EcoTec3 engines available in the completely redesigned 2014 Silverado 1500 and Sierra 1500 pickup trucks are the most fuel efficient and technologically advanced engines in the market.
These engines utilize an advanced combustion system that maximizes the potential of the direct injection (DI) fuel system, active fuel management (AFM), variable valve timing (VVT), two stage oil pumps and other technologies. The dexos1™ 0W20 oil supports these technologies and is an enabler for the improved fuel economy performance that is exhibited in these products.
Question: Are other automobile manufacturers recommending 0W20 engine oil for their products?
Answer: Some other manufacturers are already recommending 0W20 engine oil for their products. General Motors expects this to become an industry trend and more automobile manufacturers will be recommending the use of 0W20 engine oil in the future.
Question: What do the numbers 0W20 represent?
Answer: 0W20 represents the standard SAE measurement of oil viscosity. Viscosity is a measurement of the oil’s resistance to flow. The more resistant the oil is to flow, the higher its viscosity.
Question: If dexos1™ 0W20 oil is recommended for my vehicle’s engine, do I have to use it?
Answer: Yes. As an example, the 5.3L and 6.2L V8 EcoTec3 engines available in the 2014 Silverado 1500 and Sierra 1500 pickup trucks, were designed, engineered, validated and EPA certified using dexos1™ 0W20 oil. This is the ONLY oil approved for these engines.
Question: What if the engine Is low on oil and dexos1™ 0W20 oil is not available to top off the oil level?
Answer: There are many different retailers nationwide that sell GM licensed oil products that meet the dexos1™ specification. Refer to the first section in this Bulletin: dexos 1™ and dexos 2™ Information Website
If you are unable to locate a retailer, then a GF5 Synthetic grade 0W20 oil that meets the dexos1™ specification, such as Mobil 1™ 0W-20 Advanced Fuel Economy synthetic oil can be used. It meets or exceeds International Lubricant Standardization and Approval Committee (ILSAC) GF-5 requirements.
Question: Can another oil such as 5W30 that is cheaper and more widely available be used in place of dexos1™ 0W20 oil?
Answer: No. The 5.3L and 6.2L V8 EcoTec3 engines available in the 2014 Silverado 1500 and Sierra 1500 pickup trucks were designed, engineered and validated to run using dexos1™ 0W20 oil. This is the ONLY oil approved for these engines.
Question: What if a different viscosity oil is added to the engine other than dexos1™ 0W20 oil?
Answer: If a different viscosity oil is added to the engine other than dexos1™ 0W20 oil, GM recommends that an oil change be performed as soon as practical, but no longer than the next scheduled oil change. in order to return the engine to the original dexos1™ 0W20 oil factory requirements.
Question: Will using a different viscosity oil other than what is recommended damage the engine?
Answer: It is not possible to comment on every type and viscosity of oil that is available. Some higher viscosity oils may impact engine and fuel economy performance. Likewise for example, using a lower viscosity oil in an engine that requires 5W30 oil may not provide appropriate lubrication and may impact engine and fuel economy performance.
Always follow GM recommendations and only use the oil specified in the GM Service Manual and/or the GM Owner Manual for the appropriate Model Year/Vehicle/Engine.
Question: When will dexos1™ 0W20 oil be available to Service Agents (Dealers)?
Answers: In the United States, dexos1™ 0W20 oil is currently available at retailers nationwide in 1qt and 5qt containers.
In the United States, Mobil 1™ 0W20 oil is currently available in quart/drum/bulk through the GM Oil Program.
In the United States, Customer Care and Aftersales (CCA) will release pricing and availability for ACDelco dexos1™ 0W20 oil as soon as it becomes available.
In Canada, Mobil 1™ 0W20 oil is currently available in 1L and 4.4L sizes through the GM Oil Program.
In Canada, Customer Care and Aftersales (CCA) will release pricing and availability for ACDelco dexos1™ 0W20 oil as soon as it becomes available. Refer to GM of Canada Bulletin GMP2013-149.
Question: Can Service Agents stop using/selling other oil weights in lieu of dexos1™ 0W20 oil?
Answer: That’s an individual decision that GM Service Agents will need to make based on the vehicles they are servicing. GM Powertrain has approved the use of 0W20 oil for applications specifying 5W20 oil.
Question: What is the oil with filter capacity for the new 5.3L and 6.2L V8 EcoTec3 engines used in the 2014 Silverado 1500 and Sierra 1500 5.3L and 6.2L V8 EcoTec3 engines?
Answer: The oil with filter capacity has increased to 8.5 qt in order to support the advanced technology used in the engines, ensure proper engine oil cooling, aeration control and vehicle performance.
Question: Can dexos2™ 5W30 be used in a Duramax® diesel engine?
Answer: No. The Duramax® diesel engine requires using the API CJ-4 specification, 15W40 and in cold weather 5W40 oil. This specification oil MUST be used. Refer to the section in this Bulletin titled: Duramax® Diesel Engine Oil
GM Oil Life System in Conjunction With dexos1™ Supports Extended Oil Change Intervals
To help conserve oil while maintaining engine protection, many GM vehicles are equipped with the GM Oil Life System. This system can provide oil change intervals that exceed the traditional 3,000 mile recommendation.
The dexos1™ specification, with its requirements for improved oil robustness, compliments the GM Oil Life System by supporting extended oil change intervals over the lifetime of a vehicle.
If all GM customers with GM Oil Life System equipped vehicles would use the system as intended, GM estimates that more than 100 million gallons of oil could be saved annually.
