Quote Originally Posted by Dunnie View Post
In my opinion, good new oil and a decent new oil filter every 5,000Kms on EVERY small turbo diesel can extend the life of the engine by at least half as much again as the cheap oil/ unbranded filter/ 10,000Kms service interval alternative. 400,000Kms with luck.<snip>
Hmmm, I didn't mention cheap oil that I can recall.

Fact is 10,000km is an absolute doddle in most circumstances on CI-4 and CI-4+ oils in a Tdi. I'm talking quality oils, not cheap crap.

We have ULSD fuel these days so soot levels remain low and TBN is never taxed. Hell, I have test results where TBN is virtually unchanged after 20,000km.

Even the old school Nissan indirect injected TD42T can easily exceed 10,000km OCI's on CI-4 mineral oils without taxing the oil. 20,000km on synthetic is easy (recommended OCI is 5000km) Soot levels remain low as do all wear indicators.

Most times, depending on things such as sump capacity, trip types, trip lengths and state of tune, you aren't extending engine life by changing oil at 5000km, merely wasting money, IMHO, but if it makes you feel better......

and FWIW, the air filter is far more important regarding engine life than a full flow oil filter, which at best catches shrapnel from a component failure, but does little true oil filtering regardless of brand. (ok, there are three exceptions that I know of)
Real oil filtering is only performed by a by-pass filter such as used in the TD5.