PDQ OWNERS FORUM

what are your recommendations for going to a synthetic oil. Manufacturers?

They are all basically the same. Use the recommended viscosity and DO NOT use a synthetic blend. Mobil 1 is usually priced OK at Walmart.

I agree with Terry, as long as they are 100% synthetic, they are all good. I use Mobil 1 in the cars but I don't think they make a 15W-40 diesel oil. They make 5W-40 which will not hurt the engines. The 5 is just a 5 weight equivalent when started in a very cold environment. The main reason I don't use it in the boat is it can be a challenge to find sometimes. I use Shell Rotella T6 15W-40 Full Synthetic Diesel Engine Oil. Seems to be easier to find. Be careful not to get T5, it is a blend.

I've been using Amsoil 15-40 full synthetic oil for years.
I'm very satisfied, and with testing you can go to 300 hrs.
Change oil filter every 100 hrs.
Roger on Teamwork 100 hp hull 65
Going 300 hrs.lessens the cost of an oil change.
Generator also. Roger on Teamwork

You are talking about the 4jh3-te yanmar? Or a newer 75 hp? Everything I've seen is "conventional only" for these engines. But I only read it on the internet, so it must be true!