View Full Version : 10W30 vs SAE30

02-17-2007, 12:21 PM

Last year was my first year and I always used 10W30 for my 15 and 19 hp kawisaki engines. However my dealer says that 10w30 is harder on them then sae30. Is this true? I get 10w30 for a good price by the case and would prefer to keep using it. The manual says both 10w30 and sae30 are both ok.


02-17-2007, 01:01 PM
I think your dealer is an idiot but i dont really know for sure. The oil viscosity discussion has been here before and it seems that 10W30 or sae30 are both acceptable. I run 10W30synthetic and have had 0 troubles after 350 hours on my 17hp kawi. Keep the oil changed at regular intervals and you should be fine. BTW if you look at your engine owners manual it shows that both oils can be used.

02-17-2007, 01:36 PM
Below says it all, I believe your dealer was referring to the part in red.
It's not harder on them but could burn a little more oil between changes, So continue as you like but check your oil a little more often as stated.

02-17-2007, 01:37 PM
:hammerhead: Here;


02-18-2007, 05:37 PM
10W30 always.....

I used SAE30 before because that's what the sticker on the engine said.....wrong....I blew out the base gasket (big one around the perimeter of the engine). If you are in a colder climate then absolutely 10w30 unless you want problems....SAE30 will be like molasses when cold, which is not good to start against....

10w30 will still act like SAE30 when hot.

02-18-2007, 06:19 PM
Using SAE 30 Oil did not cause your oil leak.

Bill Kapaun
02-18-2007, 09:02 PM
10W-X starts off as a 10 weight base stock.
Viscosity Index Improvers are added to make the "X" part.
VII's prevent the oil from thinning out as much when it gets hotter.
The greater the difference between the 10W part (or whatever the W number is) and the "X" part, the more VII's are required.

A straight weight oil therefore, contains more lubricants and less additives than a mult-weight oil.
OTOH, oil technology has improved so much in recent years, that today's 10W-30 PROBABLY lubricates better than 30 weight from the60's.

Synthetics are a different animal, requiring few to no VII's.

Also keep in mind, a multi-weight at cold temps will probably provide better start up lubrication than a heavy straight weight. Use either under the appropriate conditions.

02-18-2007, 10:29 PM
10W-X starts off as a 10 weight base stock.

This is not true....Although a multi-grade oil will start with a base stock less than the "x" number it is not the 10W number.

The number before the "w" in a multi-grade is only a relative number that says how easy it will turn over in colder temps. So the lower the number the easier it is to turn. The vicosity number or weight index is the classification of its kinematic viscosity measured at 100 degrees C.

Lucforce - Why did using SAE30 in cold temps not create higher pressures and leak through weakest point being the gasket?