OK to use synthetic oil ?

[crazy charlie]

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.

Be very careful about switching from conventional to synthetic on any "not new" engine. Synthetic oils do not have the qualities and additives that keep the gaskets plump and sealed like conventional oils do.I am living proof that trying to take better care of my engines by switching to synthetic did nothing more than start a dripping leak where there was previously no leak.This 1st happened on a 100k mile Jeep which had a privileged babied life .Thought it would be a good idea to switch to synthetic at that time and I immediately discovered that where I may have had some slight seepage ,which is common an gaskets, turned into an immediate leak.I changed the synthetic out immediately within a a few days.The new leak improved with the use of conventional oil however I had slightly leaking gaskets for the next 100k miles.My next Jeep owned from new I used conventional oil except in the cold winter months where my remote start would not crank enough times to start the Jeep with conventional oil so I would schedule a synthetic change just before the cold weather hit so the engine would crank easier with the synthetic and remote start would function.The motor is currently at 150k and I just did the synthetic change ,as I always have ,and noticed that my valve covers started leaking for the 1st time so the synthetic has gotten me again. I think I will add some "stop leak" to the synthetic before changing it to see if any improvement.Stop leak contains concentrated additives that are found in conventional oils so I will give it a try .That being said,I would recommend a synthetic blend over a full synthetic for any engine that is not new.
Now as far as new engines that call for synthetic, they are manufactured with different type of seals and gaskets that are more compatible with synthetic oil use.Charlie

 

[bnicol456]

I'd recommend Kawasaki K-TECH, it's synthetic blend and is formulated for small air cooled engines. I service several commercial Z turns with well over 3K hours on the clock with it. since new....
If you're dead set with full synthetic, i'd look no further than Amsoils 10w30 small engine oil https://www.amsoil.com/p/amsoil-10w-30-100-synthetic-small-engine-oil-ase/

I can't imagine why a superior product would be discouraged. I have used full synthetic in my mower (and car) since the first change. Walmart sells synthetic at a great price and it is highly rated.

 

[barny57]

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.

I think most the oil nowadays is a blend

 

[Scrubcadet10]

I can't imagine why a superior product would be discouraged. I have used full synthetic in my mower (and car) since the first change. Walmart sells synthetic at a great price and it is highly rated.

$13.00 a quart for amsoil, or $6 a quart for K-Tech from my John Deere dealer.
Several commercial mowers running over 3k hours, on KTech with no usage between changes is good enough for me and the customer.

 

[jcworks]

I'd recommend Kawasaki K-TECH, it's synthetic blend and is formulated for small air cooled engines. I service several commercial Z turns with well over 3K hours on the clock with it. since new....
If you're dead set with full synthetic, i'd look no further than Amsoils 10w30 small engine oil https://www.amsoil.com/p/amsoil-10w-30-100-synthetic-small-engine-oil-ase/

Scrubcadet10, after reading all these posts I'm torn between continue using the regular Castrol conventional oil I've always used or go with the Kawasaki blend. Two local dealerships all told me using synthetic was ok. BUT, they've told me totally incorrect info on a trans axle issue I had. They had no clue on that as to what was wrong and they told me everything was fine. It took a lot of back and forth between me and Bertsmobile1 on here, and talking to a Hydro Gear rep to figure it out...which turned out to be so simple. So, my main concern is the engine is a 2013. The manual just says 10w30 - 20w50. It does not even mention synthetic at all. In 2013 perhaps the synthetic craze was not as strong as it is today; or maybe those engines of 2013 were not spec-ed out for synthetics. Who knows.

 

[nbpt100]

Tell that to the equipment manufacturers that use synthetic straight from the factory in new equipment. Kohler dealers don't even receive conventional oil from their distributors anymore. The conventional Kohler 10w30 supercedes to the full synthetic version.

That is a good point. How do they justify it right from the start? Could one assume they both work to break in the engine, just one is a bit quicker. They figure many will not even bother to do a break in oil change so they just go with the syn right from the factory and keep everything a bit simpler. I am just musing.

 

[TheWB]

Tell that to the equipment manufacturers that use synthetic straight from the factory in new equipment. Kohler dealers don't even receive conventional oil from their distributors anymore. The conventional Kohler 10w30 supercedes to the full synthetic version.

Kohler oil change kits are provided by Amsoil. I have run synthetic in everything since new, all Amsoil.

 

[pwardxe126]

My TORO zero turn mower has Kawasaki 23 hp engine. 270 hours on it. 10 Years old. Been using CASTROL 10w30 or 20w50 in it, conventional oil. I've been thinking about maybe running synthetic in it this spring. Heck, everything else seems to be running ir. Got any thoughts on that anyone? I don't think I'd want to go down to 5w30 and don't know if synthetic comes in 10w30 or some such.

Switched my Kawasaki fh721v from conventional 20w50 to vanguard 15w50 full synthetic. Noticed smoother running and better oil pressure when the engine gets warmed up.

 

[grumpyunk]

If your engine does not need synthetic to protect for extreme heat or slow flow when cold, then you can use conventional oil without any problems. OTOH, if you want to spend more per oil change, synthetic is perfectly fine to use.
The engine was designed with conventional oil as the prospective lubricant. It should do fine. Synthetic will not buy anything unless you reach temperature extremes where regular oil would tend to degrade.
I have yet to use any synthetic in my Kohler CVs, with conventional 10W30 as the spec'd lube. They have lasted since 1988 and 1997 respectively, don't knock or use oil between changes. I do not baby them, as they were designed to run at about 3k rpm for hours, and they do fine. When drained, the oil is still brown, not black. I use any brand, whatever is on the shelf. I have used Stens filters without problem, along with some from auto parts stores that matched.
This is not rocket science, and the oils today have better additive packages than when the engines were designed.
If you want to spend money on very very high quality oils, have at it. You are just lining the pockets of those who sell that product. Check with "Project Farm" YT channel for unbiased comparisons of oil brands. You may be surprised at which seem to perform better than some usual suspects. Oil should not cost $10/qt. If it does, a LOT of that is in profit.
IMO.
tom

 

[Scrubcadet10]

Scrubcadet10, after reading all these posts I'm torn between continue using the regular Castrol conventional oil I've always used or go with the Kawasaki blend. Two local dealerships all told me using synthetic was ok. BUT, they've told me totally incorrect info on a trans axle issue I had. They had no clue on that as to what was wrong and they told me everything was fine. It took a lot of back and forth between me and Bertsmobile1 on here, and talking to a Hydro Gear rep to figure it out...which turned out to be so simple. So, my main concern is the engine is a 2013. The manual just says 10w30 - 20w50. It does not even mention synthetic at all. In 2013 perhaps the synthetic craze was not as strong as it is today; or maybe those engines of 2013 were not spec-ed out for synthetics. Who knows.

10w30 Synthetic Blend, like KTech should cause no issues.