5w-30 in mower that calls for 10w- 30? (Synthetic)

[slomo]

Most important thing is the outdoor temp the OP's mower will see. Since the OP is talking about a mower, obviously used in the spring and summer, I would use 30w up to 100F like the Briggs chart indicated. If the temp is 40F or less use 5w-30. For real mowing conditions 30w to 100F and 15-40/50 over 100F. A good HD Diesel 15w-40 can't be beat for typical summer mowing conditions.

5w-30 will shear like mad at 100F. Don't care what super duper wonder fake synthetic is used. Remember these are air cooled engines.

 

[vronline]

Except you can look at a VOA of Briggs and Stratton synthetic oil and see it's almost a 5w20... So, to me, using a HDEO 10w30 is much thicker already. I see absolutely no need to jump up to 15w40. I'm sure it's fine, but not what they recommend.

I know a lot of folks on here use 15w-40, but both Honda and B&S spec Xw30 and it seems to work well for those using it. I wouldn't personally use a conventional Xw30 in a B&S, but that's just me. But a synthetic 5w-30 or 10w-30 should be all you need for either a Briggs or the Honda the OP is inquiring about.

 

[TiredTrucker]

I have had very good luck using 10w30 synthetic in all my air cooled engines for quite a long time. Even my Yamaha EF2000 generator that gets used both on my semi truck year round in everything from -20F to over 100F with the same 10w30, and also used for various tasks around the property. It has around 800 hrs on it now. All my mowers get a fill of 10w30 every spring. And the zero turn has to operate for several hours at a time, even at above 100F temps, mowing areas of the property. That Kawasaki twin engine still runs great after several years.

 

[JimPghPA]

Bubbatime, from the chart above 15W-50 is the only oil rated for use up to 120 F.

 

[NH73]

Looks like another small engine manufacturer got away from only recommending 30 weight oil. No 40 weights in the recommendation, but that now at least have a good argument to why you can use it.
Originally Posted By: bubbatime
Directly from their website:

We recommend the use of Briggs & Stratton Warranty Certified oils for best performance. Other high-quality detergent oils are acceptable if classified for service SF, SG, SH, SJ or higher. Do not use special additives.

Outdoor temperatures determine the proper oil viscosity for the engine. Use the chart to select the best viscosity for the outdoor temperature range expected. Engines on most outdoor power equipment operate well with 5W30 Synthetic oil. For equipment operated in hot temperatures, Vanguard 15W50 Synthetic oil provides the best protection.

-Use SAE 30 in warmer temperatures of 40° F and higher (5° C and higher)
-Use SAE 10W-30 for a varying temperature range of 0 to 100° F (-18 to 38° C), this grade of oil improves cold weather starting, but may increase oil consumption at 80° F(27° C) or higher
-A synthetic oil SAE 5W-30 is the best for very cold temperatures of -20 to as high as 120° F (-30 to 40° C) providing the best protection at all temperatures as well as improved starting with less oil consumption
-Use SAE 5W-30 for very cold temperatures of 40° F and below (5° C and below)
-For continuous-use, such as commercial lawn cutting or pressure washing, use Vanguard 15W-50 Oil (temperatures from 20°F to 130°F)
-Use a high quality detergent oil classified "For Service SF, SG, SH, SJ" or higher.
-Do not use special additives.
-Synthetic oils are an acceptable oil at all temperatures. Use of synthetic oil does not alter required oil change intervals.

 

[Climb14er]

In my thirty year old Toro, that's leaking a little oil, I run the Wal Mart 10W-30 Synthetic. And in the five year old Honda OHV, I also run the 10W-30 Wal Mart Synthetic.

In both engines, the inexpensive Wal Mart 10W-30 synthetic does the job very well.

Save money and no complaints.

 

[Mantooth]

T6 is all I use in my zero turn Hustler 23hp. Change it every spring.