2012 Forester oil consumption

Pretty well all the FB25 forester use oil, but Subaru has designed the AVCS system to function correctly using 0w-20 full syn oil, by changing to different grade you can cause problems ie running rough, heavy fuel consumption, and even the eng light can come on.

I just top mine up with 5w-30 as Subaru states in between oil changes.

Keep in mind guys the new FB motors are a lot different internally compared to the old EJ motors hence why Subaru recommend the use of 0w-20 full syn oil.

The New-generation FB Subaru Boxer engine
・ The bore and stroke, the basic structure of this engine, have been reviewed to achieve a compact combustion chamber as well as a long stroke, which was difficult previously due to chassis mounting conditions in boxer gasoline engines. This allows high combustion efficiency, and generates a sufficient mid-low speed torque with improved fuel efficiency and practicality.

・ Improved fuel efficiency has been achieved through optimization of intake port configuration and the addition of partitions inside ports, the use of TGV (Tumble Generated Valve), and the use of an EGR (Exhaust Gas Recirculation) cooler.

・ AVCS (Active Valve Control System) is used on both intake and exhaust valves. For the intake side in particular, an intermediate lock system allows valve timing to be advanced or delayed for precise control over intake and exhaust valve timing, allowing maximum engine performance in output, fuel efficiency, and exhaust emission.

・ The use of lightweight primary moving parts, such as pistons and connecting rods, and a highly efficient and compact oil pump provides an approximately 30% reduction in friction loss and improves fuel efficiency and revolution response.

・ Cooling has been optimized by using separate engine cooling circuitry for the block and the head, resulting in improvements in fuel efficiency and output characteristics.
 
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^ Gidday Clint

The same should apply to the series II SG and MY10 2009 SH we have. Both have the EJ-253 donk. Both have the AVCS (variable valve lift technology). Both OMs specify that the "recommended" oils is 0W-20. We run both on 5W-40 fully synthetic ...

No problems with rough running/idling.
No problems with high fuel consumption (the SG gets better than the advertised figure on the open road - 7.3L/100 kms! The SH isn't too far off it - 8.5L/100 kms with 4 adults on board) - considering that these figures are a fantasy, at best, I reckon that's pretty good!

Never had a CEL, and hopefully never will ... :poke:
 
Oh well 10W-40 for me as recommended by Subaru Australia. @ 140K km and no oil use and a clean exhaust pipe (no black) and no piston slap I'm confident of my choice.
 
Before I had a change of career (got bored of being in an office), I had a new Audi A3 (2005) company car and that thing used to drink oil for fun. It was on something like 18,000 mile service intervals and it would use about 2 litres of oil in between services. I kept saying to the garage that it wasn't right and they just referred me to the manual that stated it could use way more than that and still be within spec. It did this without any change in oil consumption right up to 90,000 when I gave the car back.

I think it is definitely to do with increasing service intervals, trying to get better fuel economy etc as others have said.

When you have grown up with the mind set of an engine using/ burning oil is bad, it is hard to change.

Now my 99 Foz on the other hand, has 140,000 miles on it, gets and oil change every 5000 miles and doesn't use a drop in between oil changes.
 
Gidday BB

What grade of oil do you use in your Forester?

What grade was being used in the Audi?

I reckon it's the ridiculously light oil being recommended by the manufacturers that is the problem.
 
I've just switched to 10W/50 from a recommendation from my new mechanic.
I queried him & he just looked at me & said trust me, you're gonna love it.

And for what he's done for a few people I know he done work for, why would I doubt him :iconwink:

Anyway time will tell :)

Regards
Mr Turbo
 
^ How many Kms on the clock, Mr T?

Roo2 is now at nearly 110,000 kms, and it is running 5W-40 fully synthetic Shell Helix Ultra. It has used no oil in 9,000 kms since the last service.

I always ran 10W-40 in Roo1. In my much older cars back in the 1970s, I ran 20W-50. But those engines were (relatively speaking) agricultural. Ran 10W-40 in the Kimberley, but everything else ran 20W-50.

In both our SG and SH OMs, Subaru states that 20W-50 fully synthetic is OK for use in extreme conditions. That's pretty heavy compared with the 5W-40 we currently use, and hugely thicker than the "water" that Subaru recommend for both cars - 0W-20!

It is incomprehensible to me that Subaru (or any other manufacturer ... ) would recommend such thin oil for use outside the Arctic Circle in winter ... :poke: :raspberry: :iconwink:.
 
^ A mere spring chicken, mate.

I know it doesn't get as cold up there as down here, but you should be fine with 5W-40 FS.

As NL said, and it's my understanding too, that the greater part of the wear on an engine is during the first minute or so of running. Even if it's 45°C, the engine is still 'cold' compared with normal operating temperatures.

During this time, you want the oil to be as thin as possible, consistent with having any lubricating properties at all!! For a country like Oz, that translates into about a 5W or 10W oil at its thinnest.

For fine tolerance engines, the maximum viscosity needs to be around 40 weight. Maybe 50 if the engine is on its last legs, or is routinely used in very high ambient temperatures (> 40°C, and mostly over 30°C).

Shell actually make an oil specifically for Japanese made engines! I only found this out about a week ago, researching Tempo's problem. Info here:

https://www.shell.com.au/products-s...cars/find-right-car-oils/helix-hx7/hx7aj.html

Based on all this, plus my personal experience with Subaru EJ engines over the last 20 years, I reckon that a 5W-30, 5W-40 or 10W-40 are suitable. I would tend towards the lower viscosity oils in (relatively) new engines - i.e. with less than 150,000 - 180,000 kms on them.
With higher mileage, older engines, or engines that have been ill-treated and are worn, a 10W-40 or even a 20W-50 would appear to be more suitable. The same goes for engines that are routinely used in harsh conditions.

High ambient temperatures -> heavier oil such as a 20W-50. If dusty as well, reduce the service period for oil, oil and air filters down to maybe every 7,500-8,000 kms. If extremely dusty, reduce the service interval down to around half normal, about every 5,000-7,000 kms. If both extremely dusty, and hot conditions, reduce the intervals even further. I would not think that less than every 5,000 kms would ever be warranted, but I would also be inclined to do this every 3 months as well.

With the easy running that Roo2 has had, I have no problems letting the time run, as long as the oil is still looking clean and healthy (not going dark brown; no frothing/emulsification; no sign of sludge build up in the engine or on the inside of the oil filler cap; no sign of higher than normal engine operating temperatures). These things are all good. The fully synthetic oil I use looks and feels better at 9,000 kms and 18 months old than almost any other car I have had did at 6 months and 5,000 kms ... They all ran on normal mineral oil, including Roo1.

Back in the days of my hot Morris 1100, I would do a full service every 1,500 miles (about 2,500 kms). This would include oil change, new filter, wash the oiled sponge racing air filters, new plugs and points, set the tappets, service the distributor cap and advance/retard mechanism, adjust the carburettors (twin 1 1/4" SU semi side draught), adjust the carbie float levels and linkages.
Geez, things are a tad simpler these days!! :iconwink: :ebiggrin: :biggrin: :poke:.
 
Hi Ratbag

I am running 10w/40semi synthetic in my foz, which is the recommended viscosity for my NA engine.

The audi that I used to have would had been running 5w/30 oil and as it was a company car, I never experimented with anything else. It was a real shocker for me at the time to have this new car drinking oil- perhaps that is how they manage the 18000 mike service interval, half the oil is changed during that period from you topping it up.



Ratbag said:
Gidday BB

What grade of oil do you use in your Forester?

What grade was being used in the Audi?

I reckon it's the ridiculously light oil being recommended by the manufacturers that is the problem.
Click to expand...
 
Gidday BB

That's what I thought you would say.

That's the grade I ran in Roo1 ('93 Impreza) for its entire life of nearly 18 years and 234,000 kms (except for the running in period ... ). I was using fully mineral oil though. It never used any oil or water between services, which were sometimes rather far apart ... :iconwink:.
 
Barnboy said:
It was a real shocker for me at the time to have this new car drinking oil- perhaps that is how they manage the 18000 mike service interval, half the oil is changed during that period from you topping it up.
Click to expand...

But new cars always use oil initially, that's called 'running in'. Ok so these cars are run in at the factory! If you call 8K red line on a bench for 2 minutes running in then......

For me it's the tried and true method. It's like bodywork repair, it's all in the preparation.

  1. first 1,000 kms (1K) a base mineral 0W 'running in' oil with no friction modifiers or detergents. No revs above 4K with a strict warm up routine.
  2. Oil/Filter change
  3. from 1K to 3K standard mineral 5W detergent oil with no friction modifiers.
  4. Oil/Filter change
  5. from 3K to 500K km Castrol 10W/40

As all the piston rings and contact surfaces have been properly seated with the metal cast offs already removed. The engine will never use any oil again unles you abuse it.

But unfortunately new cars are usually never run in properly and the current friction modifier oils never allow the rough metal surfaces to wear smooth so they always drink oil as the pistons rings have never been seated properly!

;)
 
^ Goodness, gracious me!

174 PAGES of posts on that one topic ... :poke: :puke:.

Maybe they should all switch to 5W-40 FS ... :iconwink: :biggrin: :cool:.
 
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