I agree with Chris on the oil. However, oil wouldn't have contributed to the injector & fuel pump failure. If that's the only problem you've had in 3000 hours, you ain't done bad
On the "ordinary setting" i.e TCW3 you can use any good quality TCW3 certified oil. For ultimate protection, use XD100 on the TCW3 setting. In your heavy usage situation this might be the way to go.
PS which fuel pump failed, the low or high pressure?