Briggs and Stratton recommends their Synthetic 5w-30 in everything they make for all applications. It's their best oil.

Here is a link that might be useful: Briggs Synthetic oil

i have had execellent results using mobil 1 .i have a 91 honda used commercially with at least 6000 or 7000 hours on it using only modil one. it still runs like new.

5W30, synthetic or not, is not the best choice for a lawnmower engine. It is a winter oil. A good 30 will do a better job in an engine that is going full bore in a hot, dusty environment.

Chazo:

I have been using Syntec 5/50 in a Kohler 14 hp. installed on a large commercial Snapper walk-behind since it was new in 1995. I mow 2 acres about every 9-10 days all season long. The engine starts just like it did when new -- on the first pull after choke -- and compression and power are all like new. I change oil/filt. once year in fall just before putting the mower away. The oil always looks pretty clean when I drain it.

When I purchased the big Snapper, I mentioned I planned to use synthetic oil, and the resident chief mechanic told me it would ruin the engine. I replied that he was full of crap, and he was. I am reasonably sure synthetic will more than double the life of any engine with a pressure lube system. Maybe triple. Synthetic seems to practically eliminate carbon buildup in an engine, keeps the plug clean, and will give you better fuel economy to boot.

Don Yellman, Great Falls, VA

Briggs and Stratton recommends their 5w-30 Synthetic for all temperatures. It's their recommendation not mine. Newer oils meet tougher requirements and are better able to handle various conditions. Check out the Briggs info below.

Here is a link that might be useful: Briggs oil info

that seems to be a generator page

That's interesting. When did that change, then? Briggs has always recommended a straight 30W, with an added statement to the effect of "using a mulit-vis oil such as 10W30 is acceptable with the warning that it will cause higher oil usage" (or something very similar, at least).

The little chart would clearly show 30W as preferred with mulit-vis and other weights shown extending the range below 0F. Or is my memory playing tricks on me?

All of my small engines get 30W Pen. as does the Farmall A.

MoTim,

If you care to check it out, recent versions of Briggs owners manuals recommend 30wt for 40 degrees F and above. Synthetic 5W-30 or 10W-30 is recommended for any temperature range.

You can check out the oil recommendation chart on page 7 of the link below.

Here is a link that might be useful: Briggs and Stratton owners manual

It is interesting that Briggs is recommending synthetic oil at all, and I think it is high time if they have come around to it.

But it is not clear to me whether this recommendation extends to splash lubricated engines as well as pressure systems. I have always followed the practice of using straight 30W in my splash engines, and synthetic in the pressure systems with an oil filter.

If Briggs is now saying 5-30 synthetic is also superior in splash systems, I am willing to consider that. I never could see why it wouldn't work. But I see no reason why Briggs proprietery oil should be any better than Castrol, Mobil, or any other synthetics from major manufacturers. The very best synthetic still comes from AMS Oil of Superior, Wisconsin, which first invented and tested this product back in the 70's. I started using synthetic in my cars and trucks in the 80's, after talking to a race driver who was using it.

Don Yellman, Great Falls, VA

Thanks, adkinsca, that is a useful link. I agree that synthetic oil is good stuff. I've already switched to Mobile 1 in vehicles and have been thinking about switching to M1 in the mowing equipment, too.

i use mobil 1 20-50w -not 5w-30 in my mowers. i agree-5-30 is too light for mowers

Discussions about oil never reach any conclusions. Go to the Briggs and Stratton site and do a little research. You will find that they recommend their Synthetic 5w-30 for all their air cooled engines in all temperatures under any conditions. Apparently they feel the Briggs anmd Stratton Synthetic 5w-30 meets a higher standard that allows them to make this recommendation for air cooled engines.

I use Mobil 1 in both my lawn tractor and my push mower sence new > The push by the way is a 3.5 HP clasic garbage engine > New in 92 > Runs like new > Uses no oil and oil comes out clean at change time

If you plan to use the mower only in temps 40 degrees and above - 30W is fine.

If you plan to run the mower below 40 degrees, you can use a multi-weight (believe Briggs recommends 5W-30). I would probably go ahead and use a synthetic since you don't have an oil filter and the cost difference for 20 ounces of oil is pretty minimal. I have never used a synthetic but from what I have read Mobil 1 is pretty much universally accepted as a good performer. Make sure you use the viscosity recommended by Briggs.

Jim

Forgot > The mobil 1 is 10-30 synthetic

I have used M1 5W30 in my Honda 5.5 hp OHC engine since purchasing it in 2000. I change once a year, at about 50 hours (I have an hour meter on my mower). It has never used a drop in 50 hour change intervals; this Spring, I used M1 0W30 that I happen to have in my stock. This oil now has 28 hours on it, and has used none yet.

20W50 oil sounds way too thick to allow the oil slinger to perform efficiently. Its just easier to sling thinner oil, especially when it is cold. Thinner oil gives you more power and burns less fuel. Just think about that slinger dragging through thick oil every revolution of the crankshaft, and how much extra throttle the governor is laying on to maintain a given rpm setting.

Next year, if I have no oil burning this year with my 0W30, I just might try 5W20. In any case, I believe that synthetic 5W30 M1 is an absolutely safe recommendation for most lawnmower engines; at least until they start burning an excessive amount. My mower is 5 years old, and has just over 250 hours on it, and no sign of usage yet. I would follow the recommendation of Briggs and Stratton, and not use dino multigrades.

Thank all of you for your insight. As some of you have noted the Briggs web site has a very helpful chart that recommends multi-grade synthetic for all temperature ranges. I also checked with a well-established local dealer and he too recommended synthetic, but only after running 30wt for about the first 50 hours. He indicated that this would help seal and seat the engine properly before introducing the synthetic.

I am sure that a straight 30wt would do fine in general. But I intend to get as many years as possible out of this mower and it seems that the improved performance and technology of a synthetic would do it best.

Thank all of you for your insight. As some of you have noted the Briggs web site has a very helpful chart that recommends multi-grade synthetic for all temperature ranges. I also checked with a well-established local dealer and he too recommended synthetic, but only after running 30wt for about the first 50 hours. He indicated that this would help seal and seat the engine properly before introducing the synthetic.

I am sure that a straight 30wt would do fine in general. But I intend to get as many years as possible out of this mower and it seems that the improved performance and technology of a synthetic would do it best.

"Just purchased a Toro SuperRecycler with the Briggs Quantum engine. I want to get the maximum life from this engine and so I am considering running synthetic oil in it. Any recommendations or comments?"

Sounds like a very good idea and it follows the manufacturers recommendations.

Here is an update on my use of Mobil 1 0w-30 oil in my Honda 5.5 hp OHC lawnmower. The hour meter says my last oil change back in the early spring now has 60.3 hours on it. The oil still has a nice golden color, and it has yet to burn a drop. I am using this mower to clean leaves out of my yard weekly, and am undecided on whether to change the oil now, or wait until early Spring when it will probably have almost 75 hours on it. I am amazed that it could run this many hours and not use a drop of this 0w30 oil.
As an experiment, I might change out this synthetic oil for a 5w30 non-synthetic oil and see if it burns any.

Considering that Chazo will be using his mower in south Texas, I see no call for multi-vis oil. I would run Opti-4 30W under those conditions. Here in VA, with cold fall and spring use as well as hot summer, 10W30 would be indicated, whether regular or synthetic.
Jellyman; I hope you don't actually believe that Ams invented synthetic engine oil.

I've put about 4 hours on my B&S Intek 18.5HP already. It shipped from the factory filled with oil, but I wanted to switch to a synthetic to prolong the life of this lawn tractor. Is this a good time to change the oil? Or am I not really through the break-in period yet? Either way, I usually like to stock up on the supplies that I need and I was going to purchase a synthetic and keep it on the shelf until I was ready for it.

The manual suggests an SAE30 for engine oil. Is this the same as Mobil 1 0W30? I'm a bit oil illiterate when it comes to figuring out what might work instead of exactly what the manufacturer suggests.

I'm located in S.E. Louisiana and rarely if ever see temps below 30 degrees. It does happen, just not that often and I probably won't be riding the tractor around if it is that cold.

I believe I would keep 30W in it. A good non-synthetic is Quaker State 30HD in the green container. 30W and 10W30 are definitely different. 10W30 flows like a 10W when cold and like a 30W when hot. To accomplish this, temperature-sensitive 'thickeners' are added. 30W is all oil, with no thickeners. If you were in a cold climate, 10W30 would be indicated, but 30W is better in warm climates. You can find synthetic 30W oils.

Thanks saxman1 - I'll keep an eye out for a good straight 30.

I have a Toro lawn mower from 1988 with a Tecumseh tvs100 4 stroke, I was thinking about switching from straight 30 to a synthetic such as 5w30 or 10w30. Which is better for summer use? The outside temp would be from low 50s to low 90s. Thanks

Can anyone tell me if you can use 4 cycle marine oil in your lawn mower?

Technically, if it conforms to the specifications dictated by the owners manual/engine manual, I don't see why not. Now, there's no reason I can see why it should preferred.

What weight marine oil do you plan on using? Most marine oils are something like 25W40 weight, a little thick for a lawn mower engine. If you can get an appropriate weight marine oil, no reason why it would not be satisfactory.

Reference my posts above, my Honda GCV 160 OHC engine on my lawn mower has gone through two more yearly oil changes since those posts. 2006 oil change was 64.7 hours, and 2007. a couple of weeks ago, was at 54.3 hours. In both cases the oil level was still right on the full mark and the oil still looked good. Oil used was Mobil 1 5W30. Temperature range was 30 degrees to 98 degrees. I used mower a bit less this year because I acquired a lawn vac and used it for some of the yard clean-up I used to do with the mower.

If synthitic oil is the end all be all, how did older engines ever last on dino oil? I'm not arguing that syn is better, but it seems like a lot of people think an engine won't last with dino oil. How many cars are running around with over 300,000 miles all on dino? My father, and myself both have lawn mowers that are over 20 years old, still running great, and have never had synthitic oil in them.

You are absolutely correct about engines lasting a long time with regular oil. As long as you have a reasonable OCI, an engine will last just as long on dino as synthetic. Exceptions might be turbocharged engines and certain known sludge prone engines.

Changing regular oil at 3000 to 5000 mile intervals will get you 200,000 to 300,000 miles. I used Mobil 1 synthetic from the time it came out back in the 1970's until I retired about 6 years ago. When it was first marketed, it was said to be good for a one year or 25,000 mile OCI, and I took them at their word. I changed my oil once a year, at 18,000 to 20,000 mile OCI's. Never had an engine problem in almost 25 years of one year oil change intervals.

I agree that synthetic has no advantage if you are going to change it as if it were regular oil and not going to extended intervals. When I retired about 6 years ago, I went back to using regular oil, and 6 month OCI's, which are usually at 2500 to 3000 miles.

I recently purchased a lawn tractor with a Kohler engine. I accidentally put it 10W30 instead of the recommended 30W 4 cycle engine oil. Can I run the mower with the 10W30 until I need to change it or will it damage the engine?

You should be okay. The Kohler website recommends 10W30 as an alternative to 30 weight, and is good for temperatures from 0 degrees to over 100. Is this a new machine, or did you buy a used one? If new, it is usually recommended to change the oil at the 5 hour mark. Be sure to do this. If you want to use regular 10W30, be sure to monitor the oil level closely, as some engines are said to use more of this oil than straight 30. If you use a synthetic multigrade, the consumption should be more in line with a straight 30 weight.

I have been told by a cub cadet dealer that cubs oil brand is designed to with stain a higher oil temperature for air cooled engines. Car iol is lower temperature because it is a water cooled engine. Please answer, Thanks

My question is i was told my a cub cadet dealer that their cadet oil is better for lawn tractors because he said their oil is designed not to break down as easy as i was using car oil. He said it wasmade to withstand a higher temp. for air cooled engines.Please help me out as i have always used car oil 10/30. I wonder maybe they could give you trouble if you had a warrenty issue with the engine?
Donald J Mitchell
djmitch@windstream.net

I've used generic synthetic 10W-30 or 5W-30 (like from Walmart) in my air-cooled mower, changed once every year or two depending on usage. I just check the level periodically in the meantime. If the manual says a synthetic multi-weight can be used it should be fine regardless of brand. I've never heard of a warranty being successfully voided based solely on the brand of oil, as long as it meets the stated requirements. Actually, I seem to recall that there are consumer regulations against that - at least for cars.

Gentlemen, thanks for your contributions to this discussion string. I believe I have something to add.

The Multi-Vis additive that "transforms" a straight-weight motor oil into a multi viscositiy oil is NOT a lubricant. An auto-engineereering professor conveyed this many years ago. He conveyed that since the multi-vis additive is not a lubricant that it's presence decreses the lubricating effectiveness of the oil. In high performance applications, a straight weight motor oil is better.

I always thought it was more important to use a non detergent oil for these type engines because there is no oil filter and this type of oil will not suspend the dirt in the oil. any thoughts to this?

You must use HD (high detergents )in a gasoline lawn mower engine. In a matter of fact all gasoline engines need detergents to keep the engine clean.
Non detergents are used in things like air compressors.
Draining the oil removes the dirty oil. This depends on the use etc.
Look at your engine manual.

I use Castrol edge advanced full synthetic 10w30, I haven't had any problems with it, the oil isn't the cheapest, but it is a brand i know I can trust.