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What weight oil is recomended for the M38 I am hearing differnet grades from everyone I talk to...thanks

Jon

Oil, Cough Medicine, and other elixars are always hard to nail down because of all the bull crap, hokey pokey and hearsay surrounding them.

The bottom line on oil selection is simple. Which label do you like and choose the correct weight for the season.

The thing is all oils on the shelf have to meet the minimum standards set forth by the engine manufacturers and the many rating agencies such as the Society of Automotive Engineers (SAE). Therefore when you choose any of these oils choose those that meet your engine manufacturer's recommendations. Those manufacturer standards are what the engine builders base their warranty on. So, as I said above pick a label you like with the correct use rating and weight for your engine and the seasonal average temps.

On modern engines the manufacturing clearances are usually at a much closer tolerance then our 3/4 century old engines. The multi-weight oils work well for them. The problem with the multi weight is for our looser engines the low viscosity at cold startup does not give our rotating parts a lot of lubrication since the oil is thin when cold.

Any modern straight weight oil meant for gas engine is satisfactory for you to use and the temp versus weight chart in your manual still applies today.