Oh boy, don't get me started... :laughing:
I totally agree, Ric.
I don't give a rats a$$ what anyone else thinks either.
An oil change costs me around $30.
I'll do mine at about the 3,500 mile mark, or once a year for me.
I am an old school mechanic, and I will not trust that an oil can go 15k. Ever.
And, in the case I am wrong (I am not), what's the harm in changing more frequently??
I'm with you Paul. I'm a firm believer in 5,000 mile intervals with synthetic oil, regardless of driving style.
Background: I'm a tech at a BMW/Audi/mini shop, prior to that I was an Audi dealer tech. Been doing this... quite a while. I can tell you from my experience, oil changes are such an inexpensive ounce of prevention.
BMWs have varied on what their "Condition Based Service" calls for for oil change intervals. I've seen them reset to as low as 11k, as high as 24k. I can assure you that these engines do not respond well to going that long. Sludge build up (not just on turbo cars or direct injection) is a big problem, causing problems with variable valve timing components. Cars that followed the factory recommendations also seem more prone to suffering issues with other valvetrain components (variable valve lift). The V8 cars, especially turbos have their valve stem seals lose pliability and end up smoking like Yellow Cabs. Also, when the oil filters stay in past 10k, it's not uncommon for them to "hourglass", or suck down onto the oil filter housing cap (filter insert, not spin on filters). More on this with aftermarket filters below...
Audi's long stuck with 10K oil changes (when they switched to synthetic). I've not seen the same issues with them that BMW has had.
Minis also run 15-20k intervals, and have similar problems as the BMWs. We've had customers tell us when they bought the car at the dealership, the sales people pushed hard that they'd never even need to open the hood between services; ironic because as the cars get out of warranty they're using a quart of oil every 800-1000 miles, only hold less than 5 quarts, and don't have a (low) oil level sensor...
I'll echo the sentiment that for ~$40 every 3K miles, it's worth it for the peace of mind.
Also, I like Krex' graphite oil lubricant. Do not confuse it with additives which can change the oil chemistry.
As for oil filters, NAPA Gold (made by Wix).
I can only chime in with experience on the BMW filters I see, but I've not seen good results from any parts store filters (especially any made in China or Poland - I'm not knocking the country of production, I'm knocking whoever gave them the standards the parts were made to). These filters are the worst for collapsing, even at "Normal" oil change intervals. I've seen some literally tear through, no longer filtering anything. Also, we see multiple cars a month where the o-rings that came in those kits have gone square and literally pump oil out of the filter cap. And sadly, I looked at a receipt once a customer had - they paid nearly the same amount for that garbage filter as they would have a quality filter from the DEALER.
15,000 miles is pushing it, but probably still safe depending on the oil, filter and engine. Newer direct injected gas engines are notorious for oil dilution with fuel, so no way I would take one of those to that kind of mileage. Older engines with intake port fuel injection have no problem going 10k miles between changes with the appropriate oil and filter.
A good friend of mine drives a lot of miles for work (35k/yr) and he has been doing 10k mile oil changes for many years. None of his vehicles have had any engine issues or used any oil by the time he gets rid of them around 150k miles.
Changing oil more often certainly won’t hurt anything, many say it is cheap insurance, but extending the interval won’t hurt anything either if you use the proper oil and filter. I don’t drive that many miles and have multiple vehicles, so I change them each once a year. This usually ends up being around 5k on the highest one and about 1k on the lowest one.
To me, how you use the car probably has the biggest influence on how long you could get away with for intervals. If you're doing a lot of highway driving, you've gotten the car into it's operating sweet spot and could probably stand to leave it in longer. If you're doing lots of hops/cold starts/lack of full warm ups, then change it more as you're inducing more unburned fuel and moisture from not reaching proper operating temp. You could have the best oil ever designed, but to me I'd still want to get all that not-oil crap out of there.
3,000 was what oil change places started to tell people. I'll let you wonder why. Here is how often you should change your oil.. open your owners manual and see what the people say who made the engine. There is simply no reason to change it more often unless for some reason you enjoy doing it and wasting some of your money.
You might be able to go 15,000 with full synth and a good filter. Depends on many things such as how long you drive, how aggressive your driving it, etc. Most modern vehicle's take this (and many other things) in consideration and the computer will tell you when you need to change the oil. However, it does not consider that you may be using synth oil.
I would argue against that one (Manufacturer recommending what's best for the engine). As it was explained to me back when I was at a dealer training class (regarding other manufacturers maintenance plans at the time). You have to remember that each oil change counts against the car's total carbon footprint (and maintenance costs). If each car gets one less oil change under warranty, that's (let's say) 7 quarts less of oil that counts against their numbers. Multiplied by however many cars, you can see how much better they look when you trim that out. Keep in mind also that their goal is to get the car through the warranty period. I think of BMW less as "Brought My Wallet" (though it's that too...); I'll play Mike Phillips here and quote myself, since I haven't seen other people using the phrase - it's more like: "Barely Made Warranty". The majority of the repairs we're doing are on cars with 60k-120k. Unless manufacturers have a powertrain warranty past 50k, I find it hard to believe their focus is 200,000 mile longevity. Their focus is power to weight and fuel economy, and however they have to get there. Hence the increasing use of Zero W Thin oils.
This is all just my opinion from what I see with the cars I work on every day. I will happily admit I know nothing about how asian or domestic cars tolerate different oils/filters/intervals. I'm no engineer, so I can't say how the various additives or binders or modifiers in oil come into play at various mileages, I can just tell you - the cars of owners that follow lower intervals have less big issues than those that don't.
I'm replying on my work computer - later I'll try and dig out pictures of the inside of an X3 that was dealer serviced and followed the service light to the letter. Then another picture of a similar year/mileage 335i that did about every 5k with the same oil.
