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Mixing types of engine oil

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Old 04-12-2018, 11:40 PM
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dayunbao
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Default Mixing types of engine oil

I'm planning to do some basic maintenance on my 996, like the changing oil, oil filter, air filter, and cabin air filter, but need to order the parts. Since my engine oil is getting a bit low, and since I want to hit some canyon roads this weekend, I was thinking to add some new oil while waiting for the parts to arrive. I have no idea what oil is currently in the car, though. Will adding some Mobile 1 0W-40, and so potentially mixing different types of motor oil, have any drastic short term negative effects?
Old 04-13-2018, 12:42 AM
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Looneybin
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I think 5w40 is the approved viscosity
other than that, it won’t hurt to mix brands, despite what you may read here
Old 04-13-2018, 08:31 AM
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Mike Murphy
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If you use Mobil 0-40, you have the best chance of matching factory fill. I don’t think there is any risk in mixing oils.
Old 04-13-2018, 09:17 AM
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dporto
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Originally Posted by murphyslaw1978
If you use Mobil 0-40, you have the best chance of matching factory fill. I don’t think there is any risk in mixing oils.
^^+1... "mixing oils" or topping off with a different oil is not going to cause potential problems akin to mixing coolant (coagulation, etc...). Just make sure you don't overfill...
Old 04-13-2018, 09:59 AM
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Tyler H
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Mixing oil is fine. Running out of oil is what yields drastic short term negative effects.
Old 04-13-2018, 11:19 AM
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Spork
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Mixing of oil will cause a chemical reaction resulting in production of toxic fumes and possible spontaneous combustion.

It will also cause immediate IMS bearing failure, RMS leakage, AOS intermix, cylinder bore scoring, dropped valves, pulling to the left under braking, premature clutch wear, and your radio to play nothing but rap.







Oh wait, I thought today was the 1st. Never mind!
Old 04-13-2018, 11:27 AM
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fpb111
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Originally Posted by Spork
Mixing of oil will cause a chemical reaction resulting in production of toxic fumes and possible spontaneous combustion.

It will also cause immediate IMS bearing failure, RMS leakage, AOS intermix, cylinder bore scoring, dropped valves, pulling to the left under braking, premature clutch wear, and your radio to play nothing but rap.







Oh wait, I thought today was the 1st. Never mind!
You forgot spontaneous combustion, cracked coils and immobilizer malfunction.
Old 04-13-2018, 11:28 AM
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wyovino
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Originally Posted by Spork
Mixing of oil will cause a chemical reaction resulting in production of toxic fumes and possible spontaneous combustion.

It will also cause immediate IMS bearing failure, RMS leakage, AOS intermix, cylinder bore scoring, dropped valves, pulling to the left under braking, premature clutch wear, and your radio to play nothing but rap.
You forgot to mention the dreaded sun visor delamination,
Old 04-13-2018, 11:46 AM
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Barn996
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Originally Posted by Tyler H
Mixing oil is fine. Running out of oil is what yields drastic short term negative effects.


And overfilling can cause issues.
Old 04-13-2018, 01:54 PM
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porschedog
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Mixing oil will also cause spontaneous cowlicks.

Just make sure you change it every 60 days before it goes bad. (j/k!!! although I have had a tech swear that is the best plan to help put his kid through college)
Old 04-14-2018, 12:51 AM
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dayunbao
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Awesome, thanks everyone!

A friend told me it would cause my car to download more RAM, which was my major concern.



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