Oil change intervals?

[JRL]

MOBIL MOBIL
No oil is called MOBILE look at your bottles guys

[oragex]

Daily short trips 4000miles using synthetic
Daily long trips 8000 miles

[benrk]

Annually, in the fall, somewhere near 10tkm, usually German brand filter like Mann, Mahle or Bosch, 0W40 full synthetic oil typically Liqui Moly, but also Mobil 1 (European car formula) or Castrol Edge (European made) if out of LM.
For the oil I'm mainly looking for VW 505.00 approval as it was an update to their oil specs after the 1.8T motors developed oil sludge issues with the earlier formular, sounds familiar?

[abscate]

All my fleet get annuals, the BZW X3 E83 gets the most miles at 15k. I use Mobil 1 or Castrol all synthetic.

The T5 uses a quart in about 6 months, mostly seeping. The BMW uses about 1 quart in 7500 miles.

I converted three of my cars from conventional to synthetic despite all the Internet fables of seal leakage

My Beetle convertible is the 1.8 turbo and is sludged. Fume. I treated it with Bell Engineering desludge product and it improved but I get a low oil pressure alarm above 85F after hard running at idle. It will need the pan dropped and a new oil pump eventually. Ugh. 800 USd at dealer, so I'll do that job.

No data yet on the new P2.

[JRL]

If you own (not lease) and plan to keep the BMW, I would NEVER let any car go 15K miles without an oil change, NEVER!

[precopster]

My 2000 non turbo uses about 2 litres between changes however to me it's all about colour. The blacker the oil the more carbon is mixed with the oil. Carbon is abrasive.

I change every 9-10 thousand kms or 5-6 thousand miles with full synthetic. This mileage coincides with a colour change. On the wife's 850 colour change happens much earlier so is impractical to keep up with. The valve stem seals have perished badly and that means a lot of carbon mixing with oil.

[mouseskowitz]

'02 V70 2.4T with 140K every 7500 miles with Mobil 1 0w40 and I can't remember which German filter. I was wondering if I could take it to 10,000 and had Blackstone analyze the oil at 8000. A couple of the metal levels were borderline as well as the viscosity being just under the low side. So, I think I'll keep it at 7500.

[precopster]

Mouseskowitz 0W40 is doing more harm than good during warmer months. I can see why your metal levels are high. I would personally stick with 5W 40 during Winter and 10W 40 during warmer months.

[Tonyx]

precopster, that doesn't make sense. Why would 0W40 cause more harm than 5W40 or 10W40? The 0 would flow better during cold starts and behave the same when engine warms up, I'm struggling with the statement you made.

[benrk]

Tonyx, I'm not perfectly happy with Mike's categoric statement either, but you have to put it into geographical perspective. The cold start viscosity # doesn't tell the whole story either, while a 5W20 & a 5W40 in theory should pour the same at equally cold temperatures, if you put the two into the freezer you'll find that the 5W20 will pour much more readily than the 40.
As to the claimed damage potential of a 0W40 in hot weather, put simple from my understanding the cold viscosity determines the required base oil viscosity while the hot side gets beefed up as needed with additives which get used up over time which is why you CAN run oils much longer these days than many people conventionally think IF you use a high quality longlife oil & follow car & oil manufacturers specification on operating conditions.
So if you run a thin base oil like in a 0W40 & run it long enough to use up the additives, it may well deteriorate to a 0W20 which in the American southwest or Australian interior can be an engine killer.

What puzzles me is e.g. my girlfriends Mazda having 5W20 written on the oil cap, while European manufacturers typically have a temperature chart specifying different viscosities for different ambient operating temperatures, you can't tell me a 5W20 is going to perform equally well in +50C in Baker/CA as in -50C in Yellowknife/NWT in a casually driven grocery getter.
For our use in a cooler temperate zone like Michigan or Manitoba, 0W40 should be just fine for year round use.

I'm by no means an expert on the topic nor a scientist but have done a fair bit of research on the topic, if someone here has better or contrary information that is scientifically proven & sourced, please share in layman's terms as I found it equally challenging to tell science from opinion as following & understanding the deeper science without a chemistry degree.

Thx, Ben