CX-9 oil consumption

c4racer

Member
On my last 2 oil changes I have noticed that my 2011 CX9 seems to be consuming about 1 quart every 6-7K miles.

which isn't of huge concern to me as many modern engines do consume some oil. But this hasn't been my experience with other Mazda engines or most other Japanese cars in general.

Has anybody else noticed the same?

I am using 5W20 synthetic oil and the car now has 26K miles and it close to 2 years old. We bought it new.
 
Four bangers normally consume oil espescially the older they get, but a six, not really. There is no way you should be consuming that much oil. Better get it checked out.
 
Four bangers normally consume oil espescially the older they get, but a six, not really. There is no way you should be consuming that much oil. Better get it checked out.

I respectfully disagree. My CX-9 has always used oil. More so in the summer. I use 5w20 mobile 1 full synthetic. It uses about a quart in 5k miles during the summer.
Both our MPVs growing up in the 80s/90s used a ton of oil. I was let loose at an early age to change the oil.
 
I respectfully disagree. My CX-9 has always used oil. More so in the summer. I use 5w20 mobile 1 full synthetic. It uses about a quart in 5k miles during the summer.
Both our MPVs growing up in the 80s/90s used a ton of oil. I was let loose at an early age to change the oil.

I am not a big fan of this 5W20 oil - seems way to thin to me. I wonder if 5W30 would solve the issue. Not that burning a quart in 5K miles is so much of an issue. Just wondering if the rings will end up seating better over time or if things will stay like this.

how many miles on yours now?
 
I used mobile one full synth 15w50 in my VR6 Passat, and it used just a much oil. But @ 100k miles, the engine core (excluding things like compressor, water pump, etc) was still like brand new.
 
I am not a big fan of this 5W20 oil - seems way to thin to me. I wonder if 5W30 would solve the issue. Not that burning a quart in 5K miles is so much of an issue. Just wondering if the rings will end up seating better over time or if things will stay like this.

how many miles on yours now?

Good thing that you are one of the Engineers that Mazda paid to R&D the engine creation process.

They don't just arbitrarily choose things like Torque Specs and Oil Viscosity by rolling Chicken Bones on a table...

Running a diferent oil, will make some things better and others worse.
 
Brian, the main reason our 3.7 runs 5w20 is for fuel economy, to try and squeeze out that 22mpg. I don't think there was a whole lot of r&d involved in running the thinest oil.

But I like the part about rolling chicken bones.
 
Brian, the main reason our 3.7 runs 5w20 is for fuel economy, to try and squeeze out that 22mpg. I don't think there was a whole lot of r&d involved in running the thinest oil.

But I like the part about rolling chicken bones.

Exactly. It isn't like you design an engine for a specific oil. Generally. And mine hardly if ever squeezes out 22mpg either - FWIW.
 
Just for the record, I always thought ours burned a lot of oil when in fact when you fill it with the recommended 5.5 qts it is actually just half way between add and full on the stick. At first I just added 5.5 qts when I changed the oil, then when I checked at the next oil change it was at the add mark which made me think it was a whole qt low. Come to find out when you put 5.5 qts in, it is halfway between add and full so I was only burning a half qt. You can put 6 qts in if you wish to put it up to the full mark. Of course you don't have to. Just something to think about.
 
I buy a 5.1qt bottle and a 1qt bottle at the store. Upon draining the oil, all the old oil fits in the 5.1 qt bottle with plenty of room. That is how I gauge the consumption rate.
 
all modern engines,ie cast block/ aluminum/sleeved head burn oil as a way of dissipating heat. use the right oil in the right engine and it will last it's lifespan maybe a little more with care. ya'll act like these modern engines will last forever. It's a prefab unit designed with a lifespan. we don't build classics anymore, only appliances. you want a classic, build a flat head or any old steel block with no modern features or interference from electronics. cars don't have bumpers anymore, only crush zones.
 
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I buy a 5.1qt bottle and a 1qt bottle at the store. Upon draining the oil, all the old oil fits in the 5.1 qt bottle with plenty of room. That is how I gauge the consumption rate.

That is not Scientific at all, what about the filter, what about the oil that is left up in the gallery.

I dont understand people who worry about such small things in the big picture.
 
all modern engines,ie cast block/ aluminum/sleeved head burn oil as a way of dissipating heat. use the right oil in the right engine and it will last it's lifespan maybe a little more with care. ya'll act like these modern engines will last forever. It's a prefab unit designed with a lifespan. we don't build classics anymore, only appliances. you want a classic, build a flat head or any old steel block with no modern features or interference from electronics. cars don't have bumpers anymore, only crush zones.

I'm pretty sure a new Mazda engine will last longer than a Flat Head ever would have... those old cars lasted forever, but the engines were hard pressed to go past 100K miles. Of course, they were cheap to rebuild or replace..
 
After letting the oil and filter area drain for a half hour, you advise a large quantity of oil still remains. If that is the case, we are all doomed with extremely short engine life due to deposits. A 5 minute oil change however, does support your theory. To each his own. But in my opinion, if your theory is true, then the owners manual oil capacity contradicts the oil change with filter quantity if there is still a quart of oil in the motor.

That is not Scientific at all, what about the filter, what about the oil that is left up in the gallery.

I dont understand people who worry about such small things in the big picture.
 
After letting the oil and filter area drain for a half hour, you advise a large quantity of oil still remains. If that is the case, we are all doomed with extremely short engine life due to deposits. A 5 minute oil change however, does support your theory. To each his own. But in my opinion, if your theory is true, then the owners manual oil capacity contradicts the oil change with filter quantity if there is still a quart of oil in the motor.

"Surface Tension"

Look it up.
 
On my last 2 oil changes I have noticed that my 2011 CX9 seems to be consuming about 1 quart every 6-7K miles.

which isn't of huge concern to me as many modern engines do consume some oil. But this hasn't been my experience with other Mazda engines or most other Japanese cars in general.

Has anybody else noticed the same?

I am using 5W20 synthetic oil and the car now has 26K miles and it close to 2 years old. We bought it new.

This is not a Mazda engine. It's a Ford engine so your experience with other Mazda engines is irrelevant. Mine chugs oil too. Can't find a good reason for it. Seems to run fine. I with they had a better dipstick. I can barely read it.
 
Yes mine also consumes 1 quart of oil every 6mos or 6k which is when I do my oil changes. I use synthetic also. The engine is quiet and runs fine. The cx9 isn't the only car that does that.
 
On my last 2 oil changes I have noticed that my 2011 CX9 seems to be consuming about 1 quart every 6-7K miles.

which isn't of huge concern to me as many modern engines do consume some oil. But this hasn't been my experience with other Mazda engines or most other Japanese cars in general.

Has anybody else noticed the same?

I am using 5W20 synthetic oil and the car now has 26K miles and it close to 2 years old. We bought it new.



Regulations requiring higher fuel efficiencies from the government cause OEMs to get "creative" with how they go about doing it. Internal Engine Friction Modification is one of those "creative" ways. You can go about achieving friction modification a number of different ways and some of them will lead to burning oil as a direct result - namely compression rings, piston rings and oil control rings. Essentially, reduced internal engine friction requires less energy and thus less fuel consumption - leading to higher fuel economy and a satisfied government. The trade-offs are numerous including higher maintenance engines, lower compression and greater oil burn rates.

Unless you can smell burning oil and are only experiencing higher oil consumption with each oil check at the gas station or oil change, you are probably experiencing what many newer vehicles are going through today - especially if you have a DI engine design and even more if your DI is also turbo charged. 1 quart per 6K to 7K would not bother me at all. That's approximately the same as my oil change and tire rotation interval and I have seen 1/2 quart oil burn in my new 2018 CX-9 Sig with less than 17K miles on it - and I run the best 100% fully synthetic oil ever produced. However, my CX-9 sees 4-6 thousand RPM on a somewhat regular basis in order to keep the fuel injectors clean (ha ha) and the intake valves free from carbon build-up (ha ha, too).

I run 1 quart of marvel mystery oil through the fuel tank after filling up about every 2 months. That keeps the fuel system lubed and clean from the tank all the way to the injectors and I've never had a seal or compression problem. I've scoped my cylinder walls and valves and they look nearly brand new thus far - proof the marvel interval coupled with a few full throttle romps (quite fun in the CX-9) are indeed doing the job of keeping things cleaner than average.

Yet, I'm going to see higher oil consumption between oil changes because that's the way the regulatory environment cookie crumbles. Not much we can do about that given the newer tolerances designed into these engines. However, with the need for engines to burn out more oil comes the need to keep intake valves, cylinders and cylinder walls cleaner than ever before (augmented even more so with any DI gas powered engine).
 
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