I was reading some old threads about engine manufacturer's oil recommendation vs those of the equipment manufacturer. It seems some think that the engine manufacturer knows best what to use in their engines. Well, I'm not sure I can agree with that.
Engine manufacturers make their engines and sell the same engine for many, many different applications. For instance a 5hp engine might be used on a snow blower, a lawnmower, an edger, a generator, a plow, etc and the list goes on and on. So, what do they do? Do they print a manual, or even a section in the manual, that explains the oil recommendation for each and every situation? No, they leave that up to the equipment manufacturer. I have talked with engineers from some of the equipment manufacturers, and they have people who specialize in this area, and those people are in contact and consultation with engine manufacturers, and through this collaboration, they make their (equipment manufacturer's) recommendation of what oil and viscosity to use. So, it only stands to reason, that say John Deere, makes it's recommendation for oil in a garden tractor, based on the engines intended use, ie. in a garden tractor, not a snow blower or tiller, or generator, or whatever. The engine manufacturer makes a blanket recommendation that will cover a whole range of applications of a particular engine. This is where the old 30WT recommendation came from. You could use it in almost anything and it would work. Is it the best? Well, no, it's not. Is it bad, no, not bad either, just not ideal for every situation and application. So, it makes some sense to understand that JD or Cub or whoever, does make the recommendation with a lot of thought and consultation, and it is probably more accurate, and meaningful that the blanket engine manufacturer's recommendation. The engine manufacturer has no control over what application the engine is used for once it leaves the factory, the equipment manufacturer does.
We tend to overthink things here, and I'm as guilty as anyone, but for small engines, it's hard to go wrong. Use oil, any oil, keep it topped up, and changed regularly, and you'll have alleviated probably 90% of premature engine failures. Use the ideal weight oil, with the proper ad pack mix, and maybe even use syn, and you may up your success rate to 92-95% of premature engine failures.
I think, in this day and age, with what we now know about small air cooled engines and oil, that the first good idea is "slightly" heavier oil weights, something in the 15W40 range is a good happy medium. HDEO oils have the ad pack to live in these hot running environs. If the engine has a filter, then a good syn in the 0-W30, 10W40, 0W40, 15W40 range would be ideal. I'm still on the fence about going as high as 50WT in small air cooled engines, even in the heat of summer, but I don't think it would cause a disaster at all, just probably not needed.
I've said it before and it still holds true, it all gets down to how much are you willing to spend, with HDEO gallons costing $11, and a good syn costing $25 a gallon, you have to make the choice. Do you think that the difference in protection is going to be anything to get excited about. Even if there is a difference, then it would be on the order of 2-5%, so an engine that would go 1500 hours, would go probably 30-45 hours more with syn, assuming all things equal. So to me, at least, 15W40 Valvoline Premium Blue on sale for $11-12 a gallon is a mighty hard to beat deal, but then again, so is Rotella, Delo and ST. All this is for expensive equipment, like tractors and snow blower or whatever. If you're talking push mowers, then for less than a few hundred, what does it matter, use whatever. Those 6.75 Briggs engines will run forever without even changing the oil. I know, I've got a neighbor who never has changed one, he just tops it up whenever it's low, and keeps right on mowing, for years and years and years, seriously! I can't do that, I change my push mower once a year and use either 30WT or left over 15W40.
Engine manufacturers make their engines and sell the same engine for many, many different applications. For instance a 5hp engine might be used on a snow blower, a lawnmower, an edger, a generator, a plow, etc and the list goes on and on. So, what do they do? Do they print a manual, or even a section in the manual, that explains the oil recommendation for each and every situation? No, they leave that up to the equipment manufacturer. I have talked with engineers from some of the equipment manufacturers, and they have people who specialize in this area, and those people are in contact and consultation with engine manufacturers, and through this collaboration, they make their (equipment manufacturer's) recommendation of what oil and viscosity to use. So, it only stands to reason, that say John Deere, makes it's recommendation for oil in a garden tractor, based on the engines intended use, ie. in a garden tractor, not a snow blower or tiller, or generator, or whatever. The engine manufacturer makes a blanket recommendation that will cover a whole range of applications of a particular engine. This is where the old 30WT recommendation came from. You could use it in almost anything and it would work. Is it the best? Well, no, it's not. Is it bad, no, not bad either, just not ideal for every situation and application. So, it makes some sense to understand that JD or Cub or whoever, does make the recommendation with a lot of thought and consultation, and it is probably more accurate, and meaningful that the blanket engine manufacturer's recommendation. The engine manufacturer has no control over what application the engine is used for once it leaves the factory, the equipment manufacturer does.
We tend to overthink things here, and I'm as guilty as anyone, but for small engines, it's hard to go wrong. Use oil, any oil, keep it topped up, and changed regularly, and you'll have alleviated probably 90% of premature engine failures. Use the ideal weight oil, with the proper ad pack mix, and maybe even use syn, and you may up your success rate to 92-95% of premature engine failures.
I think, in this day and age, with what we now know about small air cooled engines and oil, that the first good idea is "slightly" heavier oil weights, something in the 15W40 range is a good happy medium. HDEO oils have the ad pack to live in these hot running environs. If the engine has a filter, then a good syn in the 0-W30, 10W40, 0W40, 15W40 range would be ideal. I'm still on the fence about going as high as 50WT in small air cooled engines, even in the heat of summer, but I don't think it would cause a disaster at all, just probably not needed.
I've said it before and it still holds true, it all gets down to how much are you willing to spend, with HDEO gallons costing $11, and a good syn costing $25 a gallon, you have to make the choice. Do you think that the difference in protection is going to be anything to get excited about. Even if there is a difference, then it would be on the order of 2-5%, so an engine that would go 1500 hours, would go probably 30-45 hours more with syn, assuming all things equal. So to me, at least, 15W40 Valvoline Premium Blue on sale for $11-12 a gallon is a mighty hard to beat deal, but then again, so is Rotella, Delo and ST. All this is for expensive equipment, like tractors and snow blower or whatever. If you're talking push mowers, then for less than a few hundred, what does it matter, use whatever. Those 6.75 Briggs engines will run forever without even changing the oil. I know, I've got a neighbor who never has changed one, he just tops it up whenever it's low, and keeps right on mowing, for years and years and years, seriously! I can't do that, I change my push mower once a year and use either 30WT or left over 15W40.