Mobil 1 is bad for Subaru engines !?!

[GrantedTaken]

Mobil one is really bad in Subaru’s and famous for causing issues with Subaru’s engines.

In other cars it might be an option but it’s not a true synthetic, it’s a base 1 plant based synthetic.
For being basically a fake synthetic, Mobil 1 is really expensive as well when compared to real synthetics.

You can use Shell Rotella T6
Pennzoil platinum is good.
Castrol syntec is really good.

Someone one know just said this.
I laughed in his face, and then punched him in the face, for being such an oil nerd.

Which oil do you use?
State oil and total miles on car, please.

[mav1178]

You should also get a punch in the face for reposting someone that claims Shell Rotella T6 is suitable in a (North American) Subaru engine.

[norcalpb]

I’ve used “the oil changers” and big O tires but I think Motul feels the best.

Ford motor craft is also very good.

105k miles, never “broke in” the engine.

[atomicalex]

Viscosity and manufacturer specifications first. Then, distantly third, brand.


<— tribologist

[norcalpb]

Originally Posted by mav1178

You should also get a punch in the face for reposting someone that claims Shell Rotella T6 is suitable in a (North American) Subaru engine.

The 2.0l WRX guys love this stuff. They also talk about mixing different oils together so they may be crazy.

[wbradley]

It is widely believed on Nasioc and iWSTI that WRX and STI turbo engines will burn Mobil 1. Considering it is probably the #1 synthetic oil in North America it is probably quite safe to use. The same sites also document good results with Shell Rotella which is dyno oil so probably requireds a shorter change cycle. The fanatics enjoy changing their oil, so they buy it cheap in bulk and praise it as the turbo seems to do well and the price is right.

[GrantedTaken]

Originally Posted by norcalpb

The 2.0l WRX guys love this stuff. They also talk about mixing different oils together so they may be crazy.

Yes, that would be a valid crazy
Do they do this in hopes of placebo HP gains?
Or placebo improved wear resistance?

[wolffbite]

Followed break-in procedure as per owners manual until 1600km and noticed maybe a bit of oil consumption with factory oil, hard to tell with such a low distance traveled.

Did my own oil change after break-in with Castrol Edge 0w20 (with liquid titanium, ooh fancy) that met all the requirements/certifications per the manual, and was also on sale. Noticed no oil consumption.

Did 10,000km service and oil change at my local dealer. They used Mobil 3000 Super 0w20. I experienced oil consumption of about 1 litre over the life of that oil.

Did 20,000km oil change myself again using the same Castrol Edge 0w20 I used after break-in. I'm back to no oil consumption after 7,000km on that oil.

Considering trying out Motul 8100 Eco-lite 0w20 on my next change since I just found a local supplier and it is pretty cheap, but if I experience any consumption with that I will likely go back to the Castrol.

I don't really believe there is a blanket "best oil". Might depend on how the break-in was done, how the car is regularly driven, climate, mods etc... Find one that works for you and stick with it. You will go nuts reading all the threads on this topic trying to pick the "best", because it doesn't exist.

[Gunman]

Mobil 1, 70k miles

[ToySub1946]

2015 FRS. bought new. Now 55,000 or more miles on the car.

Oil and Filter changed for FREE by Dealerships, first three oil changes.

Since then I've used Mobil 1, 0W-20, either 'Advanced Fuel Economy' or 'Extended Performance'

Current cost of this oil is $22.88 per 5 quart container at Walmart.
Costs much more per quart if I buy a one quart container...so I keep an extra 5 quart container on hand for the extra 16oz needed each oil change.

Why do I use this brand, type of oil ? Walmart is the cheapest place to buy oil locally and Mobil 1 is the cheapest, sometimes only, 0W-20 full synthetic they sell.

I beat the shit out of the engine during the breakin period. I change oil on average every 7500 miles. Engine uses less than 1/2 quart oil during that period.

Car uses way more coolant than it does oil.

8-2-2019 update: Car now has almost 63,000 miles. Still nothing at all has gone wrong with this, just wonderful, Made In Japan vehicle. I'm currently in New York State with this vehicle. Soon to be this vehicle's 5th round trip, coast to coast, though I drove very little local miles in the past year.

[bluesubie]

Mobil 1 used to get a bad rap on nasioc because of knuckleheads modding their cars to 400 hp and continuing to run Resource Conserving 5W-30 which shears to a 20 grade even in stock WRX’s. All RC oils shear in turbocharged Subaru’s so that’s nothing new. Thankfully myself and others have educated people on nasioc and most (not all) there now realize that it’s a viscosity issue and not a brand issue.

Base stock debates are pointless because specs that an oil meets trumps the base stock it’s made from. If XOM can create an oil that meets Porsche A40 specs from Group III base stocks, who cares? XOM still uses Group III, IV, and V base stocks just as most manufacturers use a blend of various base stocks to blend an oil.

Shell has now dropped the gasoline engine API spec from Rotella T6 5W-40, even though it now has less ZDDP, although they do now offer API SN rated Rotella T6 5W-30 Multi-Vehicle which is now their gas/engine oil and has ZDDP levels safe for cats. They have also switched Rotella to their Gas to Liquid base stocks.

Mobil 1 0W-20 has been shown to do well in uoa’s posted here.

[Tokay444]

Mobil1 0w40 FS from their gas plant is probably one of the best testing UOA and protection oils made. It's all I run.

[8RZ]

I've been running M1 for 4 years, my 3 UOA reports says it's performing amazing.

[Joesurf79]

Valvoline 0-20 or 5-30 synpower full synthetic. Depends on what Advance Auto has in stock / on sale. Changed every 8 track days, doesn't seem to burn any appreciable amount for 25K miles.


I have a stack of Blackstone UOAs (every other change I'll send them a few ounces) saying the engine is happy and healthy. Low wear metal numbers, and almost no trace fuel. Happy motor!