My oil consumption

noclue119

Official Yinglish Speaker
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1990 Mazda Miata
Does your Subie Forster have 170 hp 2.5L H4, or 250 hp 2.0L turbo H4? I can see your oil consumption was progressively getting worse, even got to 3/4 quarts per 500 miles. Our VW Passat 2.8L V6 has steady oil consumption at 1 quart per 800~1,000 miles since new. And I'd been fighting with VWoA for this issue many times with all the documents. But the bottom line is, according to VWoA it's normal for that kind of oil consumption and for that they refused to fix the problem!

Thanks for sharing the experience on your Forester.

I have a 2014 manual with backup camera so only the 170 hp 2.5L H4 was available.
It is a widely discussed issue, even at consumer report
http://www.consumerreports.org/cro/news/2015/07/talking-cars-episode-73-oil-consumption/index.htm
http://www.consumerreports.org/cro/magazine/2015/06/excessive-oil-consumption/index.htm
 
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yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
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Plano, Texas, USA
Standard manufacturer response for oil consumption. Gets expensive with synthetic oil adding a quart every 1000 miles. Sooner or later youre going to have fouled plugs or a clogged catalytic converter if loss isnt due to some kind of leak.
I hear you on this and I used these long-term ill effects to urge VWoA to fix the issue on our Passat. Unfortunately they kept turning me back with standard response. Even dealer's service manager was sympathetic on this as he thought I definitely would get fixed under new car warranty with all the evidences I have had after he submitted repair request.

Face it, when you see oil consumption of any kind, you start to wonder whats going on and it becomes a wait-and-see game.
I totally agree with you on this. If I saw our new CX-5 consumes some oil for 5,000 miles, I'd start checking oil level more often than usual to make sure it won't get any worse. I don't even bother to check oil level on our Honda CR-V as it burns nothing since new.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
I have a 2014 manual with backup camera so only the 170 hp 2.5L H4 was available.
It is a widely discussed issue, even at consumer report
http://www.consumerreports.org/cro/news/2015/07/talking-cars-episode-73-oil-consumption/index.htm
http://www.consumerreports.org/cro/magazine/2015/06/excessive-oil-consumption/index.htm
This has been discussed on the other thread when Consumer Reports outlined VW/Audi, BMW, and Subaru are three suspects having oil burning issues. But some Subie lovers here insist there is no such issue and even if there was, it had been corrected many years ago.
 

noclue119

Official Yinglish Speaker
:
1990 Mazda Miata
This has been discussed on the other thread when Consumer Reports outlined VW/Audi, BMW, and Subaru are three suspects having oil burning issues. But some Subie lovers here insist there is no such issue and even if there was, it had been corrected many years ago.

Well my video shows that it isn't. And yes they gave me a new engine so we will see.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
Well my video shows that it isn't. And yes they gave me a new engine so we will see.
Actually when I questioned whether Subaru has correct the oil burning issue, I got (flame2).

I do believe with horizontally opposed engine design like Subaru's, oil is harder to drain back from cylinder walls to crankcase. Hence oil is easier to pass by the piston rings and burns out if the ring to cylinder wall tolerance is not tight enough.
 

pdlpsher

Member
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2016 Mazda CX-5 GT AWD w/ Tech & I-Active Sense
Actually when I questioned whether Subaru has correct the oil burning issue, I got (flame2).

I do believe with horizontally opposed engine design like Subaru's, oil is harder to drain back from cylinder walls to crankcase. Hence oil is easier to pass by the piston rings and burns out if the ring to cylinder wall tolerance is not tight enough.

My Outback H6 3.0 never needed any oil between oil changes (7,500 miles).
 

noclue119

Official Yinglish Speaker
:
1990 Mazda Miata
My Outback H6 3.0 never needed any oil between oil changes (7,500 miles).

If you drive an automatic and never engine brake, you will never see it. It is only if you engine brake. I tested during the 14060 - 14526 mi mark that used 0.75 QT in ~500 miles with tons of engine braking and watch the consumption level skyrocket.
 

V8toilet

Member
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2014 CX-5 FWD Touring auto and 2012 Mazda 5 Sport
If you drive an automatic and never engine brake, you will never see it. It is only if you engine brake. I tested during the 14060 - 14526 mi mark that used 0.75 QT in ~500 miles with tons of engine braking and watch the consumption level skyrocket.

I disagree somewhat because my experience has been different. I use the manual shifting often to engine brake and except for the first 3500 miles or so I have never had to add any oil to my 2014 Touring 2.5 and I'm at 52,000 miles now. I even used the thin Mazda moly too for most of these miles. Now you are correct in that increased engine braking could increase oil consumption but typically on an older worn engine. It is really hard to quantify this because just like measuring how long your brake pads will last there are so many variables that can have an effect. When I owned a CX5 Sport auto with the 2.0 I would use engine braking even more (regularly) and that engine didn't use any noticeable oil measured on my dip stick up to the day I traded it at 37,000 miles.
 

pdlpsher

Member
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2016 Mazda CX-5 GT AWD w/ Tech & I-Active Sense
If you drive an automatic and never engine brake, you will never see it. It is only if you engine brake. I tested during the 14060 - 14526 mi mark that used 0.75 QT in ~500 miles with tons of engine braking and watch the consumption level skyrocket.

As a matter of fact I use a ton of engine braking. I live on the top of a long and steep hill. On the 10% portion I use the second geat to not let my brakes overheat. I tried the same thing on the CX-5 and my wife's Acura. Neither car worked because they are designed to reduce pumping losses during coasting.
 

MikeM.

Member
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2013 Mazda CX-5 Touring AWD 2.0L
I disagree somewhat because my experience has been different. I use the manual shifting often to engine brake and except for the first 3500 miles or so I have never had to add any oil to my 2014 Touring 2.5 and I'm at 52,000 miles now.

I'm pretty sure noclue's comments were relative to the Subaru engines with known oil consumption issues. But I'll let him elaborate himself when he returns.


Many engines do consume oil under engine braking but a lot of this has to do with the design of the crankcase ventilation system. Since Mazda designed Skyactiv engines with a keen eye towards efficiency you can guess that the breather system is unlikely to allow large pressure differentials to form which is what causes some engines to consume excessive oil during engine braking.

I use more engine braking than most people and can confirm the level on my dipstick remains steady through the entire 7500 mile service interval. I've descended steep hills a number of miles using 1st gear engine braking on roads in the North Cascades that are too steep for 1st gear engine braking alone. Even in first gear I need to apply brakes to avoid exceeding the engines redline so I generally brake check to maintain around 3500-4000 rpm's (assuming the road surface is not too rugged to go that fast)..
 

pdlpsher

Member
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2016 Mazda CX-5 GT AWD w/ Tech & I-Active Sense
The CX-5 doesn't engine-brake very well and I've stopped the practice. And this is a from a driver who religiously engine-brake at every opportunity. I feel like doing engine-braking on the CX-5 does more harm to the engine than the wear-and-tear saved on the brakes. The same for my wife's Acura RDX with cylinder deactivation. Just my $0.02.
 

MikeM.

Member
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2013 Mazda CX-5 Touring AWD 2.0L
The CX-5 doesn't engine-brake very well and I've stopped the practice. And this is a from a driver who religiously engine-brake at every opportunity. I feel like doing engine-braking on the CX-5 does more harm to the engine than the wear-and-tear saved on the brakes.

The CX-5 valve timing is tuned for things other than maximum engine braking but that doesn't mean it's not worth using.

Engine braking in general is best used to descend longer grades without using the brakes (or using the brakes more minimally). Otherwise the clutch wear in the transmission will probably cost more in the long run than brakes/discs. So, don't downshift hard just because you are approaching a slow corner but do let off on the gas and coast in gear, downshifting when the rpm's are low enough to not cause a lot of clutch wear. And do choose an appropriate gear for descending long grades to avoid over use of the brakes.

It will not add any additional wear to the engine to leave it spinning at 3-4,000 rpm's down a long grade (because all engine parts are floating on a cushion of oil).
 

pdlpsher

Member
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2016 Mazda CX-5 GT AWD w/ Tech & I-Active Sense
The hill I descend on every day is 1.2 miles long and 6% grade. It might not be the ideal candidate for engine-braking as it's too short. On longer hills engine-braking is essential to prevent the brakes from overheating.
 

MidwestCX5

Member
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2015 Mazda CX-5 GT AWD w/ Tech
When you're in the automatic mode the transmission is designed to downshift so that the engine braking can assist the brakes. This will happen even during normal braking, but the transmission will downshift multiple gears if you really need to stop fast.
 

GJ-Molestor

Banned
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2011 BMW 528i, 2015 Mazda 6, 1995 Nissan Maxima Manual
the oil level goes up from fuel shear in city driving. that isn't how much oil you actually consumed.
 

jdm6593

Member
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2014 Mazda CX-5 2.0 Sport - 6MT
Our 2014 CX-5 2 liter has always burned about 1 quart of oil per 5000 miles using Mazda super-molly oil. When I started using Mobil 1, same weight (0-20w) the consumption dropped to nothing at all. At 7500 miles it is still right where I filled it.
 

GJ-Molestor

Banned
:
2011 BMW 528i, 2015 Mazda 6, 1995 Nissan Maxima Manual
The CX-5 valve timing is tuned for things other than maximum engine braking but that doesn't mean it's not worth using.

Engine braking in general is best used to descend longer grades without using the brakes (or using the brakes more minimally). Otherwise the clutch wear in the transmission will probably cost more in the long run than brakes/discs. So, don't downshift hard just because you are approaching a slow corner but do let off on the gas and coast in gear, downshifting when the rpm's are low enough to not cause a lot of clutch wear. And do choose an appropriate gear for descending long grades to avoid over use of the brakes.

It will not add any additional wear to the engine to leave it spinning at 3-4,000 rpm's down a long grade (because all engine parts are floating on a cushion of oil).

this is correct. you don't use any fuel when you are engine braking, no matter how high the engine RPM is. you are in a de-acceleration mode where the engine spins in accordance to the transmission gear it is attached to.

if you properly rev-match your downshifts with a manual car in mind, you will not cause any wear on your clutch even downshifting to 4000RPM.

the automatic transmission rev-matches on its own quite well, so nothing wrong with engine braking even if you have an auto.
 
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2013 CX-9 AWD, 2016.5 CX-5 AWD
I carefully measured my CX5 2.5L engine oil consumption for the last 5,955 (6,000 miles) when I did my oil change. My engine consumed 6 oz (0.1875 Quarts) of 0w20 PP oil in ~ 6,000 miles. This for an easy driver in a small city. Ed

my measurement is not as accurate as yours but it's close enough for me,

Pennzoil Pure Platinum w/ K&N HP-1008 oil filter (US made)

after 5,000 miles :

5 quarts in ~ 5 quarts out, no evidence of oil consumption , just sharing, your mileage may vary.....

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2013 CX-9 AWD, 2016.5 CX-5 AWD
Our 2014 CX-5 2 liter has always burned about 1 quart of oil per 5000 miles using Mazda super-molly oil. When I started using Mobil 1, same weight (0-20w) the consumption dropped to nothing at all. At 7500 miles it is still right where I filled it.

I can confirm this, I've always used the Mazda OEM moly oil, when re-filling the 5 empty bottles with old oil, I always run out of used oil after the 4th bottle. See my above post after I switched to Pennzoil Platinum, not saying the Mazda moly oil is bad, just sharing that I see the same thing as you with Mazda moly oil (1 quart loss after 5,000 miles).
 
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madar

Contributor
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2016.5 CX 5 Touring AWD, 2015 SCION XB
Moly always burned for me as well, more like a quarter quart per 6000 miles. Pennzoil didn't burn at all.