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There is a very strong possibility that you are using a backup generator, or an RV. Maybe you are not a proud camper, so we will chuck recreational vehicles out of the equation for now, but generators are a very common thing.
They are a powerful backup source that come handy in a number of situations. Of course, for any high performance generator to work, you need reliable and uninterrupted support from its engine. And when it comes to generator engines, you have to rely on a high quality generator engine oil.
Enter Cummins Onan SAE 15W-40 Oil
If you haven’t heard about Cummins series engine oil, you should know that it was released exclusively by Onan. They are the very same company that earned a solid reputation in the generators and RV industry over the last couple of years.
Since Cummins Onan engine oil was released as a flagship product, you will never have to fret over compatibility issues. We all know that generators are very sensitive when it comes to machine malfunction incidents. There could be a hundred reasons for an engine to break down. One moment, a generator is running fine, and the next thing you know is that it sputters to a relentless halt.
Special Features of Cummins Onan SAE 15W-40 Oil:
- Very popular brand in the industry.
- Known to exceed a high range of normal API classes.
- Synthetic blend for optimal performance.
- Feasible product for common RV and generator owners from all over the world.
Cummins has maintained a very strong history for making diverse products. The Cummins SAE 15W-40, besides being certified by SAE standards, is an overall better quality oil. Now, I know that we mentioned that this oil is feasible as compared to many mineral oil variants for generator engines that you can easily get in the market.
However, if you are willing to fork out some extra cash, there is no compromise on quality. This product will give you a blend of long lasting and smooth uninterrupted performance without any hick ups and spurts from your RV and generators.
You should also bear in mind that Cummins Onan SAE 15W-40 is not a full synthetic engine oil. It is a very calculated blend of mineral and synthetic oil. The reason is attributed to generator engines being small. Secondly, these engines have lower oil consumption and don’t operate mechanically as your conventional car or motorcycle engine. Therefore, Cummins decided to go with this strategy instead of sticking with a full on synthetic engine oil product.
Beware of the Energy Consumption Ratings:
Since generator and RV engines don’t operate like traditional high class motorcycle and car engines, you need to refer to the owner’s manual. As a matter of fact, Cummins and Onan published a few rules to summarize the dos and don’ts of using their engine oil.
- For starters, low ash formation is a naturally occurring by product of diesel engines. Don’t worry about it.
- Cummins Onan SAE 15W-40 follows the designated API and energy conservation rating. If you are planning to use some other brand, refer to its “Energy Conserving” chart for optimized fuel output.
- Some engine oils generate sulfuric content that is greater than the prescribed 0.0015% emission rate. If such is the case with your generator, please contact an engine oil specialist for an inspection.
- Pay close attention to the oil’s performance during winter season. There is a reason Cummins Onan mentions the letter: ‘W’ besides 10 in the product name. W stands for the oil’s performance during winter season.
10W denotes how well this oil can pump performance during cold temperatures. What happens during winter season is that oil coagulates quickly when the machine is not used for longer periods of time. All of a sudden when you start it, there are abrupt performance issues. This is another reason for Cummins Onan SAE 15W-40 to be dubbed as a blended oil with a combination of mineral and synthetic oil ingredients.
If you are doing a service check up on your Onan generator, make sure you not only change the oil, but also change the plugs and filter. Some people try to save money by not changing their oil filter. This practice garners extremely volatile results if done repeatedly.
Knowing Your Generator Rating Saves a Ton of Hassle:
In many use cases, we noted that Cummins Onan SAE 15W-40 was not the perfect product. Environment variables matter a lot too. For example, if you are located in a cold area, perhaps the 5w-30 version of the company’s engine oil.
Similarly, each generator uses a different type of engine. It is better to know your engine type before you guzzle down a brand new unopened bottle down there. Some RV and, especially generator engines use a 2 stroke engine. It depends on their category. There are 4 stroke engines too, but only you’d know that eventually.
Are there any Setbacks of Using Cummins Onan SAE 15W-40 RV Engine Oil?
On a scale of 1 – 10, this engine oil easily scores an 8.5. There were some reports where users did not get expected results as they first anticipated. However, such cases are either based on biasness, or at times when users did not follow through with other maintenance factors.
The only setback we really noticed is that sometimes it get a little hard to get the product. Some retailers do not ship this engine oil by air. In that case, you will have to wait for a couple of weeks before your package arrives.
On a related note, if you are buying Cummins Onan SAE 15W-40 RV / Generator oil from a website, make sure they have favorable shipping options. A better alternative would be to from a real life retailer. Besides, they can offer you full warranty and repair service in case you run into any unforeseen issues.
FAQs:
Is this oil for diesel engines or gasoline engines?
- As mentioned in this post, Cummins Onan SAE 15W-40 is specifically made for diesel engines.
How do I prevent moisture build up?
- By using the generator or whatever engine you have at regular intervals. If you are going to store away your unit for an entire season, make sure that you have drained the gas and the engine oil completely.
Does this engine oil work for non Onan Cummins products?
- Yes, it does!
Is 1 quart enough for my engine?
- Sometimes, depending on your generator or RV engine, it may take more than a quart. Make sure you have read the owner’s manual on that note.
If this is your first time using Cummins Onan engine oil, do share your experiences through the comments section below. We would love to hear back from you.
The Review
Cummins Onan 15w-40
You should also bear in mind that Cummins Onan SAE 15W-40 is not a full synthetic engine oil. It is a very calculated blend of mineral and synthetic oil. Cummins Onan SAE 15W-40 follows the designated API and energy conservation rating. Feasible product for common RV and generator owners from all over the world.
PROS
- Known to exceed a high range of normal API classes.
- Synthetic blend for optimal performance.
- Very popular brand in the industry.
- Feasible product for common RV and generator owners from all over the world.
CONS
- There were some reports where users did not get expected results as they first anticipated.
- Sometimes it get a little hard to get the product as some retailers do not ship this engine oil by air.
Last update on 2022-12-01 / Affiliate links / Images from Amazon Product Advertising API
