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MY07 Forester
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Discussion Starter #1
I have a low mileage Forester (around 20,000 miles ) which does consume a bit of oil in between changes - around 500ml. There are no leaks or smoke and I have been using a fully synthetic oil 5w-40. Should I use a thicker base stock to reduce this consumption or is this normal with the Subaru boxer engine? A mechanic told me that some engines do use more oil than others and it's not necessarily a problem. I'm not sure I'm entirely satisfied with this advice.

MY07 X
 

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2017 VW Golf SportWagen 5MT
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What is your oil change interval? I wouldn't worry about loosing one quart in 4,000 miles, but quart in 1k would be too much to me.

Stan
 

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MY07 Forester
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Discussion Starter #5
+1

I think 1 qt in 3,000 miles is Subarus limit for "normal" consumption.
1 quart is just under 1 litre - which equates to around 20% of the oil capacity of the sump. I'm not losing quite that much. Just curious as to why the engine is burning the oil when it's been well looked after. I'm wondering if a 10w-30 might not make its way into the combustion chamber quite so easily?
 

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2015 VW Golf R (AWD!) DSG (Automated Manual)
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The first number is cold weight, changing it wouldn't make a difference after the engine warms up (just make the oil thicker when cold, which isn't good if it gets cold where you are). No good reason to change it.

As noted above, if it's under 1qt per 3k miles, no worries. My 99 had 150k miles on it and always used 1qt in 3-4k most of the time, but I ran it hard all the time. Sold it still purring like a kitten.
 

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2005 Lifted 2.5 XT 5-Speed MT Dual-Range
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An N/A drinking half a quart (500ml) of oil between changes is bang on what it should be doing. Nothing to be worried about. Older XT's drink about a quart (1000ml) every 1300 miles or so. Not sure about the new ones.
 

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2015 VW Golf R (AWD!) DSG (Automated Manual)
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If you have an NA (non-turbo) that's using 1qt per 1k miles, you have a leak somewhere. I'd crawl underneath and look for any wet spots on the frame, engine, tranny, etc. It won't necessarily drip on the ground even, but can still be leaking. On my 99, the rear oil separator cover was leaking, leaving the clutch inspection plate wet, but I never had a drop on the ground under the car.
 

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2005 Lifted 2.5 XT 5-Speed MT Dual-Range
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If you have an NA (non-turbo) that's using 1qt per 1k miles, you have a leak somewhere. I'd crawl underneath and look for any wet spots on the frame, engine, tranny, etc. It won't necessarily drip on the ground even, but can still be leaking. On my 99, the rear oil separator cover was leaking, leaving the clutch inspection plate wet, but I never had a drop on the ground under the car.
The OP is only using a half-quart between 3,000 mile changes (I presume). That's bang on what the consumption should be.

But I agree, if an N/A was drinking a quart every 1k miles, then yes, something needs to be looked at and fixed.
 

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2008 2008 2.5i-2018 XT
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I like to see an engine use around 2 ounces or less per thousand miles. But having said that the consumption of the OP's vehicle is fine. I assume the consumption would be higher with 30 weight oil which I think is the best thickness to use.

You shouldn't go thicker than 40 wt.
 

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2007 Forester XT manual
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I'd feel a bit p****d off if I had bought a car now that used oil. No car I've owned in the last 20 years has used any and my 106,000km XT doesn't use any either no matter how it is driven, even towing. I use 5-30 synthetic as stated in the handbook.

If it's using 500mL at this stage, what will it be like with another 100k on it?
 

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02 Forester L (sold) Manual
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Ours uses 2 qts between 5,000 mile changes. :mad: Resealed engine, so no leaks. No smoke, clean plugs. Cleaned PCV valve. It's like it's disappearing into some black hole in the crankcase universe. Our Impreza did it near the end of it's life with us, but this thing only has 120,000 or so on it. Seems excessive to me.
 

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2008 2008 2.5i-2018 XT
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If it's using 500mL at this stage, what will it be like with another 100k on it?
Unless there is a ring/cylinder issue..probably the same amount.
I had a '69 Camaro that used a quart every 2000 miles. 10 years later and 100,000+ miles it was (if anything) using less.
 

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2015 Highlander AWD XLE 6AT
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I have a low mileage Forester (around 20,000 miles ) which does consume a bit of oil in between changes - around 500ml. There are no leaks or smoke and I have been using a fully synthetic oil 5w-40. Should I use a thicker base stock to reduce this consumption or is this normal with the Subaru boxer engine?
~500 ml (~17 fluid ounces) per oil change (every 3,750 miles?) is probably higher than we should expect these days, but, ~133 ml (~4.5 oz) per 1,000 miles appears to be well with Subaru’s comfortable consumption spec. Specifically, my manual suggests “abnormally high” oil consumption to be >1 U.S. qt (32 oz.; ~0.95 l) per 1,200 miles.

That's pretty high, IMHO. Even my 10 year old pickup with ~115K miles on the original 5.4l V8 uses somewhat under 1/2 qt per 1,000 miles.

I’m curious about why the 5W-40 weight oil? Subaru’s “preference” for my '09 model is 5W-30 (ref manual page 11-11), with a couple of other grades being acceptable/recommended for higher ambient temperatures and/or heavy duty applications. However, 5W-40 is not included on the list.

HTH,
Jim / crewzer
 

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2008 LL Bean (4EAT)
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I have a low mileage Forester (around 20,000 miles) which does consume a bit of oil in between changes - around 500ml. There are no leaks or smoke and I have been using a fully synthetic oil 5w-40. Should I use a thicker base stock to reduce this consumption or is this normal with the Subaru boxer engine? A mechanic told me that some engines do use more oil than others and it's not necessarily a problem. I'm not sure I'm entirely satisfied with this advice. MY07 X.
The mechanic is right and the same advice is given to many owners of other new cars who complain of oil usage. The manufacturers allow such consumption as within the normal range of variation.

But most new cars that are given frequent oil changes should burn no oil. My low mileage Scion (about 30,000 miles) uses no oil between 5,000 mile changes on full synthetic 5W-30. My low mileage Forester (about 15,000 miles) uses no oil between 3750-mile changes on full synthetic 5W-30. Those cars were bought new and I change their oil myself.

But, you don't say if you have owned your Forester since new, and given it frequent oil changes. I have noticed that my wife's 1992 and 2003 Buicks shared a common history. They were bought used when they came off lease at 40,000 miles, immaculate cars, but with only 3 oil changes showing on their records. For ever after, no matter with 3000-mile oil changes, those cars burned a quart every 3000 miles. The early long oil change intervals had taken their toll.
 

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2015 VW Golf R (AWD!) DSG (Automated Manual)
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Apples to oranges - japanese cars to domestic. Even two identical cars will have manufacturing variations within spec that will cause differences in usage. Granted, not changing your oil for 17k miles isn't good either! :lol:
 

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2014 328i xDrive Wagon 8 spd Auto
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With regular Pennzoil dino and 3000-3500 mile change interval, if I drive mostly city with short (less than 2 hour highway trips) I use no oil at all.

I've noticed that with the same oil, after two round trips Boston to DC, I've used 8 oz over 3300 miles. Which, given the amount of time I've been on the road - 11 hours, 9.5 hours, 13 hours and 9 hours, I don't think is bad at all.

I've just switched to Pennzoil Platinum Plus and will be doing two more round trips over the next 6 - 8 weeks. I'm curous to see if the consumption changes.

Mine is an 08 OB PZEV.
 
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