If you had Used Oil Analyses (UOA) for your car, then I would say you are wise, careful and analytical.

Without that, you’re just a dead blowfish taster ...

I have no doubt that in specific circumstances and conditions, that oil can "last" 20k miles. As you say, companies tend to boast the capabilities of their products. I'm guessing the 20k mile claim is based on the additive package concentration and detergents in the clean oil being reduced/consumed at some average and assumed rate. Its probably a strong oil anyway.

Now that I'm driving more than ever, I, too, am interested in extended OCIs. I used to do 6-7500k miles because my trips and use were of shorter durations. Now that I'm driving an hour to and from work, I've pushed my OCI to 9k miles and looking to try 10k miles. I've had my used oil analyzed every time. 20k mile OCI in an auto diesel of our type is too long but 11k is probably safe.

Fram filters get a bad, often deserved, rap. Their cartridge filters are probably better than their canisters. I get OE filters at my dealer for $8 so that's what I use.

To bring this back, it's not your cat!

josiahg, where did you have your oil analyzed? I would be interested in doing that. Only thing I've found so far is one website that says $60 per test, and you need more than one test to provide a trend. Got to be a better deal out there, I'm sure. Do any of the big lube or tire chains do it, and any idea what they charge? (For the record, my X is not diesel.)

Look, I don't want to advocate anyone burning up their engine. If one feels better about sticking with the conventional 3-5K OCIs and don't mind paying for that "insurance", then by all means they should do so! I'm just relating what I have tried.

And yes, thanks for bringing this back. I hope you are right about it not being my cat. Just more trouble I could blame him for. Only 18 months old and he's already 20 lbs. and eating me out of house & home.:yikes: Seriously, one youtube I watched said it usually actually is the cat when it gives this particular "cat efficiency" DTC. I'm still hoping not and will continue to investigate.
https://xoutpost.com/members/x5cat-a...762-alfred.jpg

Blackstone Labs



https://www.blackstone-labs.com/?ses...ottyp%29%29%2F


$28


While you might be on your first UOA, they have an extensive database of results. And while it is important to trend results to see if something is going on, the simple question of "is this oil worn out" doesnt need multiple UOAs.


Post the results

Nice cat! Looks like some Maine coon in him. Especially given his size already.

I use Blackstone Laboratories who ard linked to above. Your first few will just tell you the condition of the oil itself at different mileages. You don't even have to necessarily change the oil at sample time. You can draw from the dipstick (on the X5d) or partial drain. I like to let it drain for about 20 seconds prior to drawing the sample, though.

Blackstone will recommend an OCI once the condition of the oil is known and as a specific trend develops. You can take it or leave it. You'll at least be aware. I just like data.

I would have thought it would be less than $28, but OK, I will go ahead and get a test on this 11K oil that I am about to change, and share the results here. I am curious to see what the deal is, for better or worse.

Yes, that's Alfred, the wife's full Maine Coon, thanks. Likes to take me outside on daily leash walks and chase big dogs. Seriously.

Although it's more money, until you've sampled enough to know how your oil responds to extended use, I'd recommend the TBN analysis for an extra $10. The final TBN along with other indications will determine your OCI at which point you know your engine and TBN can support it. After you've established the OCI, you won't need the TBN analysis and will only monitor wear metals and stuff.

Again, sweet cat. If I were choosing, I'd get one like him but I'm thinking of going to the shelter if I do.