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15w-50 aviation oil OK in my car?

Can I use 15w-50 aviation oil in my older trucks without damage?

No.

I wouldn’t, very different demands. I’d use the cheapest in-grade oil from Wal-Mart before I’d do that.

Can you explain a little? The can says for piston engines, meets sae J1899 specs, non corrosive, etc. Someone offered me an excellent buy on this oil is why I ask.

Cleared For Take-Off!

Unless those trucks have Pratt & Whitney radial engines, I wouldn’t. Is it always very hot where you live? What do you do, hop the fence at a local airport?

I actually live near Canada, and wondered how hard it would be to start in cold weather. Thanks to all for your advice.

Even older trucks are designed for use with a particular type of oil. Using an oil other than what is recommended by the manufacturer could easily damage your engine.

We are talking about 15W-50 oil, right? When it is cold it acts like 15 weight oil and when it is hot it acts like 50 weight oil. What does your old truck call for in the owner’s manual? Let’s just assume it calls for 10W-40 for the sake of this discussion. When it is cold, the engine will function better with 10 weight oil. Having 15 weight oil would mean it is too thick to get to some of the places where it needs to get to for proper engine lubrication. When it is hot, when the engine needs the protection of 40 weight oil, your oil will be even farther away from the viscosity that best protects your engine. If your engine is a little newer, it might call for 10W-30. In that case, 50 weight oil would be even worse for the engine.

No matter how old your truck is, stick with the oil that is recommended by the engineers who designed the engine. If the truck is leaking or burning oil, you might try using a “high mileage” oil of the proper viscosity.

Richard Carlson, who played the role of Herbert A. Philbrick on the 1950’s television show “I Led Three Lives” recommended to the viewers that they use Phillips 66 Flight Fuel in their cars. This may have started the myth that what was good in aircraft engines was good forf automotive engines. However, he recommended that they also use Phillips 66 Tropartic oil. I am certain that Phillips 66 Flight Fuel is not aviation gasoline nor was Tropartic oil recommended for aircraft. As others have pointed out, aircraft engines are different than automotive engines. I don’t know how old your trucks are, but I would bet that they will run perfectly well with a multi-viscosity oil in the correct viscosity range and even WalMart’s house brand will ber satisfactory.

It depends upon what kind of oil it is. I had straight 30 weight break in oil and I ran it all Winter in Northern Maine. It probably wasn’t all petroleum base. Mineral base maybe? Since we’re talking Winter, I don’t know.

Well in most areas 15W-XX is not a good winter oil. Most car manufacturers recommend 5W-XX or 10W-XX. You would be wise to follow the manufacturer’s recommendations. Second, your car has oil specifications listed like SAE-G or some sort of letters. You need the meet or exceed that specification. Aviation oil likely uses a different set of specifications.

Air planes and cars put different requirements on their oils. The replacement schedule for that aircraft oil is going to be more often than for a modern car (same for trucks)

Don’t waste really big dollars trying to save a few cents.

By The Way, I Have Been There A Couple Of Times And It’s Pronounced {k?n?d?}!
I like their beer!

People have been killed using car parts in planes. I don’t know if the same can be said for vice versa, but it just doesn’t make sense. The plane I fly takes SAE 30 but I think the Aviation oil is designed for older aircraft engines, they are air-cooled too so the oil is critical for lubricating the moving parts. It’s not uncommon for a general aviation aircraft to be 30-50 years old. Just to go an auto parts store and spend $15 on the correct oil then avoid a huge headache down the road.