Could those of you with more oil knowledge than I possess look at these two data sheets and explain what, exactly, the biggest functional differences are between these two oils? My '82 Benz with an IDI turbo diesel doesn't use a lot of oil and holds 1.5 bar at idle so, especially in the colder months, if the differences aren't ones that will be pushing any limits I might go from 5/40 down to 10/30.
It's a half-million mile engine with 160K on it so I don't want to do any "experiments" - it seems the majority of owners are still running 15w40, and the other portion 5w40. I believe in the "as thick as necessary, as thin as possible" rule so I've been curious about a diesel 10w30 since I got the car.
The cSt numbers are smaller - both 40* and 100* - on the 30 weight, and pour point is the same. Does that mean the 5w40 isn't actually thinner on the cold side?
It's a half-million mile engine with 160K on it so I don't want to do any "experiments" - it seems the majority of owners are still running 15w40, and the other portion 5w40. I believe in the "as thick as necessary, as thin as possible" rule so I've been curious about a diesel 10w30 since I got the car.
The cSt numbers are smaller - both 40* and 100* - on the 30 weight, and pour point is the same. Does that mean the 5w40 isn't actually thinner on the cold side?
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