Synthetic oil in a riding lawn mower

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We have a 13 horse Briggs/Stratton and have always used the 30 weight Briggs brand oil. I was thinking the other day about oil(hmmm, not unusual for a BITOG fan!
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)and was curious if anyone has ever used an automotive synthetic oil in a riding lawn mower. Would consumption increase?
 
None as of yet . Have used PENNZOIL Platinum 10w-30 and a current fill of SHELL Full Synthetic 5w-30 in the recently purchased BOLENS with the 13.5 H.P. by B.&S. and no consumption . Mow close to 3 acres in some nasty heat .
 
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Dont have a riding mower but generally use synthetic automotive oil in my push mower, and my snowblower which has i think a 9.something HP Briggs motor, works fine. Only ever used 1 bottle of oil labeled for use in mowers, a straight 30wt forget the brand. Can get synth car oil on sale for much cheaper and its better oil. Conventional 5w30 burns off very quickly in the little 4HP Briggs in the mower, synth almost zero and that little rig is about 7-9yrs old now. Basically if you use conventional in these air cooled, hot running motors use a straight 30. If synth, go ahead with a 5w30 or 10w30, deals with the heat just fine.

Definitely more than good enough and probably cheaper than the Briggs oil if bought on sale.

Has worked for me as long as I've been mowing lawns and throwing snow. Motors are clean and running like new, and they're definitely not high end pro grade equipment either.
 
Air-cooled engines in extreme heat or heavy/commercial service: I would consider using a 5W-40 HDEO synthetic such as Rotella or a shear-stable 10W-30 such as Amsoil's small engine oil. The main reason to use something other than a starburst energy-conserving syn PCMO is wear protection/film strength during heavy use or extreme heat. These 2 specific oils have higher ZDDP levels and higher viscosity for hot running air-cooled engines.

I would rather use a non-syn HDEO than a syn PCMO for severe service due to the HDEO's higher viscosity and anti-wear chemistry.

Of course for regular/normal use, a good syn PCMO may be all that is really needed. Most commercial guys seem to usually be cutting grass that barely needs cut anyway, vs. some of us that push our equipment hard right up to the limits, and often. I use Schaeffers 9000 5W-40 HDEO full syn in all my 4 cycle equipment that I push hard. I use conventional 15W-40 in an old diesel tractor for field use.
 
This is my 2nd season using Amsoils 10w-30 synthetic small engine oil in my 13.5hp Briggs riding lawn mower engine.

As far as I can tell, its working great. The mower doesnt consume any oil at all, I have a very large yard I cut too and in some areas the grass can be pretty thick. The grass gets cut 2x weekly at about 1.5 hours each time.

I use the Amsoil syn small engine oil in my push mower and snowblower too.
 
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Using Mobil 1 5w-40 TDT in the Briggs 26hp ELS engine on my Scag Freedom Z. I'm in LA (Lower Alabama)and it gets unbearably hot down here, so I opted for the extra protection.
 
I wish I could find Mobil 1 TDT around here, I think one walmart has it that I have found it in. What are you guys paying for a gallon of it?
 
I have posted about this many times, look in your owners manual.... if your engine requires or calls for a 30 wt oil the use it during summer months. I have found that HDEO oils in HD 30 are by far the best for engine wear, and cleanliness... I have also seen what can happen to a "synthetic" PCMO when used in hot summer in an air cooled engine.... it makes a mess of engine internals if it becomes thin getting by rings (and it will) causing a extremely hard to remove goo/gunk atop the piston/head chamber area. I have no idea why this happens, I have seen engines with bad rings blow oil by causing very clean piston tops/head chamber area, however this has not been the case when the rings are in good shape..

This is from several engine tear downs, or head removal for routine maintenance which should be done every couple of years (2-3) to remove carbon build up.
 
I use M1 in my 20 year old Honda Self propelled mower. I have a large lawn so it gets a lot of hours every year. I change in the spring and the oil stays very clean all summer long.
 
M1 is what I tried using in a 24 HP INTEK purchased new B&S engine on a Craftsman DYT 4000. At 8 hours of use the left exhaust valve locked down from all the gook on the valve stem/guide. The inside of the head was coated thick with a goo coke substance this is oil that went past the rings, when burned in the combustion chamber caused a coke deposit that coated the entire head/chamber area, the top of the piston, the galleys inside the head where oil flows to the rockers. Also there was a black gooey type mess in parts of the bottom end, it was between a sludge, and coke more like tar.. All of this could be said to be caused by poor engine construction, defect etc, however I have seen the exact same thing in another B&S engine which was catastrophic at around 80 hours... this engine had wore the area of the crank/connecting rod/journal which I don't attribute to the M HOWEVER the exact same tar like goo was also in the bottom end of this engine, and also the valve stem, the head/chamber area, and also piston top was coated... this is not the normal carbon coating that effects all air cooled engines..

This is my experience on this subject, and I assume this is also why B&S elected so long to use 30 wt oil, I assume people having to HAVE a synthetic oil to use may be the reason why B&S makes a synthetic oil now from my reading is just a older type oil formulation mainly in the additive section... Which probably still is not as good as the HDEO 30 wt oils I posted above..

It does not bother me whatever anyone decides to use, however I would like to save people the trouble of what I have had...
 
I have used M1 10w30 EP in my JD Ztrak for its entire 339 hours, (4.5 yrs old) changing every 75 hrs. It uses approx 8 oz per OCI.
 
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