What's the deal with 12-15K oil changes?
 

We change our oil at about 3-5000 miles. MINI and BMW, and a few others require oil changes at 12-15,000 miles. When did oil manufacturing become so improved that we can start changing oil at 12-12K miles? If so then why hasn't every auto maker shifted the scheduled oil changes to 8 or 10 or 12K miles?
A friend mentioned that the extended oil change recommendation is a marketing scheme originally created by the "scheduled maintenance included" crowd and has nothing to do with the oil quality. She states that it was an algrorithm calculated which included the following variables; average length of time and miles a typical owner keeps their car and the length of the factory warranty. Once a car has reached that terminal mileage or time where the extended oil changes would incur damage on the engine, the car is in the hands of a second unwarranteed owner.
Just a thought.
Happy Driving

Full synthetic in low friction engines perhaps?

The McLaren MP4-12C supercar does not need its first oil change until 10,000 miles.

Part of it is better oil/engines which allow the car to go longer.
Other is that companies are now offering warranties with free oil changes, and if they stuck with 3-4k oil changes they would lose money.

I did A LOT of oil testing in a daily beater Honda Accord to find out for myself what the real deal was.

That car got driven about 2,500 miles a month and I did 10,000 mile oil changes.

I tested the following:
Standard dino Castrol GTX
Castrol Edge Synthetic
Mobil1
Penzoil Platinum

Blackstone labs was the analysis vendor used for all tests. I'd run one fill of the oil, then test on the 2nd fill to make sure no residual of the previous was present.

Purolator Pure One oil filters were used.

Even the base Castrol GTX was OK for 10,000 miles use, but was at it's end of life at that point.

All the synthetics were still good even at 10,000 miles with Penzoil Platinum having the best results.

I also found I could go at least 20,000 miles on the Purolator Pure One oil filter as well.

In another car that I don't drive every day I did a one year oil change test on the Penzoil Platinum and it still had plenty of life left in it after a year (only about 6,000 miles on the oil) and same Purolator Pure One oil filter.

In all tests, either none or very little make up oil had to be added. I just sold the Accord test car last week with nearly 200,000 miles on the motor and it had no issues when sold.

All my oil tests are posted over on - Bob is the Oil Guy.

Every engine is a bit different, and I plan to do some analysis on the 370z to see what it likes oil change interval wise. There's no reason to change oil at 3,000 mile intervals unless you're really tracking the car. I'm gonna start at 5,000 and use Penzoil Platinum with the Purolator Pure One filter and go from there.

you're on ther right track, i was doing this in my diesel trucks and confirming similar results.

10k is nothing on a modern engine, especially w a good full syn oil. theres a myriad of factors.

Fuel injection and instant starting alone has reduced cold start up metals and fuel dilution issues from old school cars. Oil analysis is reasonable cheap and the best way to know what's right for you and your car/usage. Also, lots of hwy= way less engine hours per 10k miles and less accumulative time at rpm.

The 3000 mi oil change has always been a gimmick. Add that to the fact that oils and engines have both improved over the last 50 years, and that's why car companies are finally starting to advertise longer intervals.

Amsoil advertises 25000 mile interval change on their motor oil i used on my Z.
I changed under 4000 always but its good to know the viscosity break down and other key aspects of the motor oil can withstand abuse for that long.

You would however want to change your oil filter every 3-4K miles as that could cause some issues rocking that for 10-25k miles!

Amsoil is the first in synthetics as well, quality stuff i used it in my Engine, Transmission and differential on my 350Z.
Also use it in my daily driver Jaguar X type in the engine and manual trans, and transfer case.

Both cars it made the transmission feel sooooo much better, also in my Z switching from Mobil 1 to Amsoil i noticed less of a friction feel in the higher RPMs... My gas mileage went up a couple miles as well :)

I ran oil filters for 20K miles (Purolator Pure One) and the analysis showed they were still fine even at 20K.

Amsoil is good stuff, but it's a high priced boutique oil. The 25K OCI assumes your changing filters which require a top up of the oil in the sump which in turn renews the additive pack. That's how it lasts so long.

Word- Personally i loved the Amsoil and K&N oil filter changed every 3500 miles...

The oil filter you were running sounds intense....

Nothing real special about the Purolator Pure One filter. I use them in all my cars. Synthetic media and a good anti drain valve. About $6 at the local auto parts shop.

I loved the K&N due to the hex head to take it off made life easier when im under there :)

Like your Avatar pic! Its like The Stig on a lawnmower!

The Stig's my cousin.

I use this on my oil filters. Quick, easy, and cheap.

http://ecx.images-amazon.com/images/...500_AA300_.jpg

Gotta love the Stig!

The only reason I am keeping the 3750 miles interval is because of possible issues with warranty