Going to change the oil in my lawnmower myself. Per the user manual it specifies: SAE 30 detergent oil with API classification SF, SG, SH, SJ, SL or higher. At the hardware store I found multiple oil brands that fit the criteria. Some are SAE 5-30W, some SAE 10-30W, and one that simply says SAE …

https://www.valvoline.com/about-us/faq/oil-types-weights-and-viscosity-faq Tester

[image] oldtimer-11: Air cooled engines get hotter than liquid cooled ones. Multi grade oils used to degrade wirh the higher temps. the length of the molecules would decrease and the viscosity would drop and that is why the manufactures would specify 30 weight oil rather than 10W-30. I have …

@B.L.E and @keith Thank you for your comments on rechargeable mowers. I didn’t intend to hijack Marnet’s thread. I hope all the advice she received on oil for her mower is as useful as all the information you gave me on rechargeable mowers.

@Triedaq , no worries, I do not consider the thread hijacked. I’m getting an education about engine oil in general and ideas for any future mower or trimmer replacements. I hadn’t expected this topic to take off like it has. LOL. But that’s fine. :grin:

[image] WesternRoadtripper1: People tell me you can’t kill blackberries, but to them I say, stop by and see my BiG lawn - where the blackberries once were. I had a 3 acre lawn like that with the same blueberries in northern NH, that I mowed the same way. However, the big negative is: before …

Odd as this sounds, it is not unusual to need to mow grass once or twice during the winter here in St. Louis, depending on temps and rainfall. I’ve mowed as late as December and as early as March a few times.

It’s simple. Whether you’re starting an engine at 20 degrees or at 90 degrees, that’s a cold start. And the oil is thinner. So you want the oil to flow as quickly as possible during that cold start to protect the engine. Thus 5W It’s not until the oil starts reaching the operating temperature doe…

@Marnet . I spent over two years in Carbondale, Illinois–about 75 miles southeast of St. Louis. By March 1st, it was spring. A lawnmower got much more running time a year than where I now live in east central Indiana. Summers were really hot down there. This was in the early 1960s when air condit…

Ok. It’s simple. Cold start regardless of air temperature. What in the world does “W”= Winter have to do with it???

5-W30 vs 10-W30 oil

Maintenance/Repairs

sgtrock21 July 8, 2018, 11:18pm 53

OK… Is Valvoline only addressing SAE (the USA)? I lived in Southern California for 3 years and have visited Southern Texas and Southern Florida in February. A temperature below 60F is rare. As far as I know engine oil is used globally. I respect your intelligence and knowledge. I consider the “experts” at Valvoline regarding this subject ignorant idiots. How about 5C-30H? C=Cold H=Hot?

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5-W30 vs 10-W30 oil

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