5W30 or 10W30 ?

Anything is possible, but it is best to read the actual oil recommendations that are written in your owners manual.

---Bob Gross---

I'd probably use 5W30 instead of 10W30 if I was up there. Here in Wisconsin the past couple weeks we've seen temperatures dipping below 0 F and we have a car with 10W30 that had a bit of a problem starting.

For both engines, the official advice seems to be that 10W30 is recommended, but 5W30 may be used in temperatures of 16 degrees C or lower. For extreme cold conditions, 0W30 conventional or 5W30 synthetic are recommended.

Smuga,

I agree with Robert. Consult your owner's manual. It states the proper viscosities of oil, for the seasonal temperatures.

GMdude

I really don't see what the difference is. The viscosity for both types go up as the engine gets warm. At cold temperatures the 5W30 still has higher viscosity than the 10W30 does when it is hot. Oil always gets thinner as it warms up. The 5W30 just does not get as thick as the

I have yet to find a lubrication engineer who can give a good reason for not using 0W30 even in warm climates.

You want to be sure to use synthetics that do not use VI to achieve the wide viscosity range.

multi-grade oils use microscopic plastic additives shaped like tiny coils to give you the two different grades of oil viscosity. as the oils warms up, the coils expand, thickening the oil to the higher viscosity on the container's label. larger viscosity differences require more of these additives, so you want as little as you can get away with, because these impurities are part of what causes the oil to break down over time and need to be replaced.

bottom line: don't use 0w40 in summer when you don't need to.

yofa - snipped-for-privacy@hotmail.com

I would use 0W30 Mobile 1 oil here in Ontario instead of 5W30 or 10W30.

Paul

recommended,

Mobil 1

Another note: A several years ago I went to change the oil in my lawn mower. Straight 30 weight is recommended. After draining I found I had only 5W30 Mobil 1. I put it in and the mower ran better than ever before. It is still running great, even with it's original plug. I pulled the heads a while ago and there was no carbon build up. I now also use Mobil 1 in my Snow Blower. My opinion is that those little air cooled engines run extremely hot. That is where synthetics really pay off. From what I have read conventional oils began to break down at about 350 degrees. Synthetics are stable up to 700 and above.

Those are called Viscosity Index Improvers. Since synthetics do not thin as much as conventional oil they (Including Mobil 1 and Amzoil) are able to obtain multi-grade oils without using them.

Many manufactures no longer recommend 10W40.

Watch out using synthetics in small engines. It can void the warranty on some. I believe it is Tecumseh that tells you not to use them in their engines. Even though it is a better oil they will tell you not to. I just cheat and use a blend. Same benefits and they don't say you can't use it. Sounds stupid but it is true.

My engines are far beyond warranty.

I just did a search and someone posted that B&S now recommends 5W30 or

This site: http://www.f Tecumseh has introduced new synthetic oils for both its two- and four-stroke engines, both winter and summer applications. For winter, the new 0W-30 synthetic oil is available in both a quart bottle and in two new Snow King maintenance kits for snow thrower engines. This oil gives superior lubrication, adds to engine life and delivers reduced starting pull force for extreme cold weather use, the company said.

For summer, Tecumseh has released a new synthetic blend for its two-stroke engines that reduces carbon build-up and extends engine life. For its four-cycle engines, Tecumseh has introduced a new 10W-30 synthetic oil that not only extends engine life but maintenance intervals as well. Tecumseh said these oils will be available in maintenance kits in late 2003.

Yes, 5W-30 should provide better cold starting without degrading operating performance. Especially since you are running synth.

John