California
Super Star Member
- Joined
- Jan 22, 2004
- Messages
- 14,975
- Location
- An hour north of San Francisco
- Tractor
- Yanmar YM240 Yanmar YM186D
There was a similar conversation with a Brit a few months back. As I recall, the conclusion was 15w40 has become the US standard for nearly all diesels here, highway and off-road, while you guys have better and more specialized lubricants available there - at correspondingly higher prices. I think the 'common knowledge' in the US for any Yanmar in ordinary conditions is just use 15w40.
I think your oil specialist guy is over-analyzing this. For fleet use across many vehicles covering many miles, sure, the issue deserves careful study to try to minimize overall operating cost for the fleet. For the way we use these Yanmars - generic 15w40 is an optimum 'good enough' answer proven by broad experience. Especially if any alternative is more expensive.
As for latest spec diesel oil - it is required by vehicle manufacturers in order to not foul the most recent smog controls. (catalytic converter?). For equipment over 10 years old without the smog devices, the new spec is irrelevant and the previous spec oil may be less expensive if you can find it. I bought a few gallons on closeout at Tractor Supply last year, so saved a little money on oil changes for a while.
I think your oil specialist guy is over-analyzing this. For fleet use across many vehicles covering many miles, sure, the issue deserves careful study to try to minimize overall operating cost for the fleet. For the way we use these Yanmars - generic 15w40 is an optimum 'good enough' answer proven by broad experience. Especially if any alternative is more expensive.
As for latest spec diesel oil - it is required by vehicle manufacturers in order to not foul the most recent smog controls. (catalytic converter?). For equipment over 10 years old without the smog devices, the new spec is irrelevant and the previous spec oil may be less expensive if you can find it. I bought a few gallons on closeout at Tractor Supply last year, so saved a little money on oil changes for a while.