5W-30 vs. SAE 30

Changing oil in the lawnmowers and snow blower. What is the difference in the two oils and can you just use 5W-30 in small engines. I have some extra at home and want to make sure I am not going to damage anything if I use it.

Manufactures recommend 5w-30 for the snow blower and SAE 30 for the lawnmower.

If you use SAE 30 in the snow blower, the oil is to thick to lube the motor correctly.

Thanks for the info: so the snowblower is good with 5W-30, what about the lawnmower, will it be ok with that or should I go and buy some SAE 30?

I use 5w-30 in all my small engines.

Air cooled motors should use SAE 30 during the summer months, I generally start using SAE 30 in my garden tractor May 1st give or take a month (depending when it has 25 hours on the oil) Spring and fall I use SAE20 when the temps are above 32 and winter 10W30 temps below 32. A small air cooled motor generates a lot of heat because air cooling is not as efficient as water cooling. Higher heat will cause the multi-viscosity oils to break down sooner.

Need SAE 30 for summer/hot weather.

I respect everyone’s input but “need” seems a little strong to me since I am on my 17th year with push mower and it has never been rebuilt. I always use Mobil 1 10W-30.
It doesnt even burn oil.

I’d go with whichever one the wife prefers.

5w-30 is fine to use. It has the same flow rate as SAE30 at normal operating temps. The way oil works is, the first number is flow rate at ambient temp. The second number is flow rate at operating temp of the engine. So SAE30 does not change in thickness no matter the temp. So the lower the first number the easier it flows in cold temps.

Hi, my name is Horace and I am a certified Petroleum Engineer. The way that multiviscosity oils work is like this. If it is a 5W-30. When the oil is cool it has the viscosity of a 5W . As the oil heats up it becomes no less then the viscosity of its largest number which in this case is a 30W. and as the oil cools it will go back to a 5W again. The reason behind multi vis oils was for the winter time so that engines would have easier startup in cold conditions before the oil gets to its maximum viscosity. So the difference between the straight 30W and the 5w-30 is that the 30W is always a 30W. When it gets cool it remains a 30W. They will both provide the same protection when they are heated up to operating temperature. If you have any questions, please feel free to write me at [email protected] I also supply the industry with the finest high quality oils on the market today

That is an incorrect statement. If the lawnmower calls for a 30W viscosity then that is what should be used either in a multigrade or straight 30w to go along with OEM warranties.