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This might sound like a dumb question, but is all BMW OEM oil the same? I'm going on a long trip and I will most likely have to add oil. Upon searching amazon, tischer and ebay it says that my 2016 550i is not compatible with the BMW OEM 5w30. I'm sure that it is probably okay. Any advice?
 

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In general, the wider the "W" and non-W number, the less stable the oil is and the more it will break down from prolonged heat. So a 0W-30 would be less stable than a 5W-30. BMW V8's run hot-hot-hot. You also might get more lifter noise with cold start-up with a 0W oil.

GM had lot of trouble back in the 1990's with lifter and bearing noise when they went from a 10W-30 to a 5W-30. For their 3800 V6's they actually changed them back to a 10W-30 in 1991. But, that was using conventional oil, which had viscosity break-down much faster and more severe than synthetic oil.

Starting in 2016, some of the six-cylinder BMW engines went to 0W-30, and some of the four-cylinder BMW engines went to a 0W-20. The engine clearances were presumably changed (made smaller) to tolerate these thinner oils.

You might be o.k., but... You can't go wrong with "RTFM." Of course, RTFM is useless without FTFM.... "Follow the ... manual."
 

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Anecdotal historical facts about oil & turbos.

I'm not going to recommend a particular grade/multi-grade of oil. I want to share some facts about oil, and turbochargers from the last time we went through this fad in the 1970's.

Multiple weights are a compromise. Low viscosity when cold, yet relatively sustained viscosity when hot.
1) Engines run @ ~ 230F. Rings/pistons maybe ~400F. Turbocharger exhaust temperatures can vary between 600F & 1300F.
2) Turbocharger bearings are lubricated right between the intake & exhaust housings. I assume modern mfg.'s have solved the problem of continued lubrication of the turbo bearings after engine shutoff. That used to cause "coking" (essentially cooking/burning of the motor oil). It would ruin the oil, destroy the turbo bearings, and lead to premature demise of those 70's economy engines.
In the old days we'd allow the turbos to cool down, by idling/slow driving for several minutes before we shut off the engine. I cringe at the thought of automatic engine shut off at lights for fuel savings on a turbocharged motor.
3) Modern engines have tighter clearances and can tolerate thinner oil between parts.
4) Crankshaft, camshaft bearings float on a cushion of oil. Thus, thicker is a little better than thinner. Unless its cold and you are just starting up the engine.
5) Lower weight = better fuel economy.
6) Important! The wider the spread in cold/hot weights for a grade of oil, the worse the compromise made in formulating the oil. Ergo, generally the lower quality of the oil itself for durability and long mileage. 10-30W oil worked great on 70's engines. 10-40W not so good.
7) Synthetic polymers are more durable, slippery, and heat resistant than natural polymers. But all detergent oil picks up dirt (One of oil's primary functions) at the same rate. Eventually, any oil will become saturated, thus dropping grit out of suspension.

As you can see, it is not easy to figure out which compromises one wants to make, when selecting the oil to run.
 

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"6) Important! The wider the spread in cold/hot weights for a grade of oil, the worse the compromise made in formulating the oil. Ergo, generally the lower quality of the oil itself for durability and long mileage. 10-30W oil worked great on 70's engines. 10-40W not so good."

My BMW dealer used to use & recommend Mobil 1 synthetic 0-40w but now recommends Shell Helix 5-30w.

I wonder if the above quote has anything to do with the change?
 

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Re: change to smaller spread in oil weights.

This is exactly what happened in the 1980's, as consumers, and I'd like to think oil product mfgr's discovered that phenomena.
 

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Synthetics are naturally multi-viscosity, requiring fewer of the unstable viscosity improvers compared to petroleum oils.
 

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Oil

Check your owner's manual:

See attached and this notation -

Alternative engine oil types
If an engine oil suitable for continuous use is not available, up to 1 US quart/liter of an engine
oil with the following oil rating can be added:
Gasoline engine API SM or superior oil rating.

If you have a good relationship with your dealer service center they may "give" you a quart to take for the ride.
 

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