Hello Tazzieman, hello Tom, to enhance my writing from above:
The most famous magazine about cars in the German speaking area is Auto motor and Sports. They took used motor oil after 50k km to the lab, may be 30 years ago, the result was: Lubrification was undisturbed after 50k km, there was no real need to change this oil! A second test may be 10 years ago had the same result! Of course the oil didn`t look like brand new, especially not from the diesel engine.
I think I have to stress, that I always take the best synthetic oils( Liqui Moly, Castrol, etc.) with the right specification from the carmaker. I think it`s clear, that you always have to change the oil filter!!! I take only the best oil filters(i.e. Mahle etc.). Because there are nearly no metal shavings in modern engines, the filter will last very long. I always buy the oil and the filter by the internet. At the dealer you pay in Germany 4-5 times more for the same stuff!
Why said Ford for the Transit 2,2l diesel engine: oil change every 50k km, or every 2- years. In the newer 2,0l diesel engines, they reduced it to 30k km. By the way, I don`t care for 2 years. I change the oil after 30 or 50k km and had never problems with it( with my sports car I changed the oil after 10 years and50k km without any problem, it looked still pretty new).
I can not understand, why you should change the oil in the 3,0l BMW engine after 15k km. My 2,2l diesel engine in my Ford transit Nugget with 2.5-3.0 tons has to work harder with it`s 360 Nm torque compared to the 3,0, biturbo diesel engine with 550 Nm torque of the Grenadier!
If you you are not a senseless driver, I can recommend all Grenadier drivers to do the oil change after 30k km, if your Grenadier has to work often very hard(towing, rock crawling, repeatedly long stretches in deep sand with high revs etc.) may be after 15-20k km. I will do it with my Grenadier after 30- 50k km, because I am a very careful driver.
With my new LR Defender, the real one, I did the first oil change after 30k km and 60k km in Africa myself on a campsite and on car park. I will do the next change before we go on our next trip to Africa with 90k km on the odometer. In 2x 9 month in southern Africa with ca. 70k km, the Defender had to work often hard in deep sand, high temperatures and steep rocky trails. The car/Engine had no problems! Even in Australia I would do the same. Because you don`t get the right oil in North/Central America or in Africa, I take the right oil with me from Germany.
So many people have unfounded anxieties all over the world and with these anxieties many people/dealers/companies make a lot of money!
I don`t have much money,that´s why I try to save money. I can´t afford mistakes: a new engine cost an awful lot of money.
Greetings from Germany, Hans!