Oil

Prop1

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I tried the search function, but nothing came up. I was wondering if anyone knows of a reason why I shouldn't use Mobil 1 0W30 oil in my 2010 Forester?
 
I take it yours is a NA petrol, not a diesel or XT? If so, it will depend on climate, usage, etc. I don't know what the weather is like where you live/drive, but in colder months a 0-30 would be fine. In hot weather, I'd be more inclined to go to a 10w-40 or 15w40 or similar, especially if you will be going on any sort of a journey. If it is an XT, this is even more important and I would stay away from 0w-30 in hot weather altogether. What is really important is that you change it regularly- I do mine every 5000km's. Diesel is even harder on oils than petrol so you do not want to skip oil changes on them.
 
It's the non-turbo petrol model. The manual states 5W30, but I've been using the Mobil 1 0W30 in my other vehicles in the winter without issue. Not having dealt with a Boxer engine before, I just thought running it by more knowledgeable people would be a good idea. The oil container states on the front that it meets or exceeds all mfg's requirements for 5W30 and 10W30 motor oils. I've done major research on oils for many years, but some oils may look good on paper, but some engines can benefit more from certain oils over others. I like this oil in the winter because it gets the lubrication to the important parts of the engine faster. Since it's a 30 weight at operating temp, it's no different then the 5 or 10W30.

If nobody has any negative info, then I guess I'll be the guinea pig.;)
 
subaru dose not recomend using synthetic oil due to the comsumption of oil trust me u will regret it latter
 
bru73 said:
subaru dose not recomend using synthetic oil due to the comsumption of oil trust me u will regret it latter
Click to expand...

I'll take my chances. I hate dino oil with a passion. Based on what I've read about the early Boxers and head gasket eating, that maybe true, but I can't accept it in this day and age.

I also found this in my manual:

Synthetic oil
You can use synthetic engine oil that
meets the same requirements given for
conventional engine oil. When using
synthetic oil, you must use oil of the same
classification, viscosity and grade shown
in this Owner’s Manual, and must follow
the oil and filter changing intervals shown
in the maintenance schedule.
Click to expand...

It wouldn't be in the manual if they didn't what it used. In the summer I will change to a higher viscosity, but with the cold winter I've been dealing with, that 0W30 will help improve the mpg and get the oil circulating fast on cold mornings.;)
 
Since new in 2003 all bar my 1st sump full of dino oil in the car i have been running mobil 5W/30 synth, my last oil change i used dino again and noticed a spike in fuel consumption. Been in all sort of terrain and conditions with no oil problems at all. Just about to run some Nulon 5W-40 synth because i got it very cheap to try, it was also recommended to me by someone in the know whos advice i trust.
 
my04tone said:
Since new in 2003 all bar my 1st sump full of dino oil in the car i have been running mobil 5W/30 synth, my last oil change i used dino again and noticed a spike in fuel consumption. Been in all sort of terrain and conditions with no oil problems at all. Just about to run some Nulon 5W-40 synth because i got it very cheap to try, it was also recommended to me by someone in the know whos advice i trust.
Click to expand...

Good to hear you've had no problems.

So far, so good for me. The 0W30 has been in for a few days. I just filled the fuel tank yesterday. So I'll report back as to whether the mpg changes. The engine turns over faster in the morning and starts faster as a result. It's also quieter.
 
bru73 said:
subaru dose not recomend using synthetic oil due to the comsumption of oil trust me u will regret it latter
Click to expand...
Sounds like bull**** to me. Subaru Australia recommends full synthetic 5w-30 oil which is all I've used for the 160,000km life of my Foz and so far it hasn't used a drop of oil. So when do the regrets start? And why?

btw dose = does
recomend = recommend
comsumption = consumption
latter = later
 
I'm using Penrite semi-synthetic. I probably use 1 litre / 5,000km, but the engine has 261,000 km on the clock. Not using any more than on the all mineral oil.

Yeah, some spelling can be atrocious, but most on here let it go - I know that if I did my 'school teacher' thing I'd probably never get any responses to my many questions. :ebiggrin:
 
Not using a SmartPhone for posts can make a major improvement in spelling;)
 
Just changed my oil to Nulon 5W-40 synth and changed the filter and have some injector cleaner running in the tank, will do the upper cylinder clean next week. My last 2 fills have been 10.5l 100k and 10.1 Litres/100k running on Dino with a bit of touring and city. I dont expect to improve it too much as its always been around 9.7 to 10 per 100k.

First thing i did notice with the oil change, quieter engine.
 
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Just did my second fuel fill with the Mobil 1 0W30 in the crankcase. The first fill showed a 1.2 mpg improvement over the dino oil. I like to run 3 fuel fills after a switch in oil to smooth out the fuel use anomalies. I hope it holds up.

But based on the improvement so far, the savings more than pays for an oil change at today's gas prices. This is the part that I don't get when people say they won't use synthetic because of the cost. In all my experience with oil, switching to synthetic will save at least the additional cost of the synthetic in fuel savings.
 
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Update: Fuel economy continues to improve. The 2nd fill resulted in a 2.3 mpg improvement over dino. Some of that could be due to warmer temperatures since the change. But the 23.4mpg city that I'm getting is the best I've ever gotten. On a trip back the first part of December; I averaged 23.9mpg, highway.
 
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I have noted the changes over 10 tanks. Fuel consumtion on Dino average 11l/100k on Nulon synth 9.5l/100k. Definately wont be running dino again but it was a good experiment to do over 12months.
 
my04tone said:
I have noted the changes over 10 tanks. Fuel consumtion on Dino average 11l/100k on Nulon synth 9.5l/100k. Definately wont be running dino again but it was a good experiment to do over 12months.
Click to expand...

I've proved it time and time again on multiple cars.

Update: The last 6 tank fulls have consistently been average within a few tenths of 24mpg, city. I was thinking of switching to Mobil 1 5W30 for the summer, but at this point I see no reason. All it will do is thicken the oil at ambient temperature.
 
Nothing wrong with Mobil 1 full synthetic.

I used to use it on a Ford Falcon and at 180,000kls before it was written off, it didn't have a single oil leak, never used a drop of oil, and the motor was always quiet!

On another car, a Toyota Rav4 SXA11, I saw the rocker cover get removed at just over 300,000klms and it was CRYSTAL CLEAN inside. It looked as though the motor had just been assembled at the factory. It was a "Learner" car, and had just started a coolant weep from the head, hence the need to lift the rocker cover. The car had Mobil1 put in it from the first 1000klm service, and every 10,000klms after that. After seeing that, I do believe full synthetic oils are the way to go.

I run Shell Ultra full synthetic in my car, and NO issues ever!
 
I just got back from a trip to Kansas City. Going there, most of the travel was in temperatures of 101-112F, and on the return it was 72-88F. Highway speed ranged from 65-80mph. The highest mpg tank average was 31.7mpg, and the lowest was 27.5mpg. The average for the entire trip worked out to 29.1mpg. Not bad for a car with an EPA hwy rating of 26mpg. I really love this 0W30 Mobil 1!
 
Gidday Brad

Prop1 said:
I just got back from a trip to Kansas City. Going there, most of the travel was in temperatures of 101-112F, and on the return it was 72-88F. Highway speed ranged from 65-80mph. The highest mpg tank average was 31.7mpg, and the lowest was 27.5mpg. The average for the entire trip worked out to 29.1mpg. Not bad for a car with an EPA hwy rating of 26mpg. I really love this 0W30 Mobil 1!
Click to expand...

Thanks for this very informative series of posts.

I will ensure that our usual servo uses the appropriate Shell synthetic oil when Roo2 is serviced in 10 days time. I am pretty sure Ross already uses this anyway, but will check to make sure.

One thought though. At those temperatures, shouldn't you be using a 10W-40, 10W-50, 20W-40 or even a 20W-50 weight oil?
By all means use the lighter oil in winter, but using such a light oil at these high temperatures could cause excessive wear (and terrific fuel economy ... :iconwink:).
The 30 weight oil really runs out at about 40°C (104°F) according to my Fox manual. So maybe this is pushing your 0W-30 oil right to the limit, or a tad past it?

Please correct me if I'm wrong.
It wouldn't be the first time, LOL!
Nor would it be the last ... :rotfl:
 
I'm using Penrite HPR10, semi-synthetic 10W50. I like the lower cold rating but still has a 50 hot rating for max protection for an older engine :)
 
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