2nd Gen CX-9 (2016-2020) High mileage club, how's it holding up?

:
2005 Mazda3
I've been keeping my eyes on the 2nd Gen CX-9 for quite some time. To me, reliability is something that I put into consideration as I usually like to keep a vehicle for a long time.

Any how, for those who have had their 2nd Gen CX-9's, how's it holding up? Anyone with 80,000+ miles on the vehicle yet?


Any common issues to look out for? How's the transmission holding up? How's the engine(I've read about some people having issues with carbon build up, to be remedied by hard driving and/or some solvents into the intake valves) ?

*New: Any coolant leaks observed? (we've had a few members on here who had coolant leaks which resulted in needing a brand new engine, would be nice to get more feed back on the community from higher mileage 2nd gen's and see how your engines are holding up)

The skyactiv Transmission is relatively new(CX-5 seemed to have some problems after about 50k miles), and even more so the skyactive turbo 2.5 liter debut with the 2nd Gen CX-9. I was wondering how it looks after roughly 4 years.

TIA.
 
Last edited:

Montanaman

Montana/Arizona
:
2018.5 CX-9 AWD GT
I threw this question out a bit ago and had a few responses over 60-70k miles with no powertrain issues. The N/A version of this Skyactiv 2.5 had been basically bullet proof from what I read on the early CX-5's and others. Some of those are over 150k miles at this point. I think the carbon build up thing is overblown in general and Mazda has some technology in there to combat it. I think if you run good gas in it most of the time and run an additive through there every 10k miles it should not be an issue.
 

sm1ke

Work In Progress..
Moderator
Contributor
:
Canada
:
'18 CX-9 Signature
I threw this question out a bit ago and had a few responses over 60-70k miles with no powertrain issues. The N/A version of this Skyactiv 2.5 had been basically bullet proof from what I read on the early CX-5's and others. Some of those are over 150k miles at this point. I think the carbon build up thing is overblown in general and Mazda has some technology in there to combat it. I think if you run good gas in it most of the time and run an additive through there every 10k miles it should not be an issue.
I wouldn't say the carbon build up thing is overblown, it's just more likely to present itself early in certain conditions. If you're in a climate that experiences "extreme" conditions (hot and humid, or very cold), and your daily commutes are so short that the engine doesn't have an opportunity to reach operating temps during the drive, your car will be more prone to producing "blow-by". Blow-by is excess oil/fuel/water vapor that is reintroduced into the intake manifold. When the engine reaches operating temps, it becomes hot enough to burn off most of the blow-by condensation that has settled onto the intake manifold valves. If the condensation is not burned off and is allowed to settle, it hardens and causes the carbon build up issues. Some people have installed aftermarket oil catch cans to catch some of the blow-by, thus prolonging the period between intake valve cleanings. In my experience with a 2.5L DI engine and over 140,000 kms, I never once had to do a valve cleaning because my commutes were long enough to get to operating temps most of the time, and I live in an area that experiences both climate extremes. I did not install an aftermarket oil catch can on that car.

The detergents in the fuel and any fuel additives will clean out the small amounts of build up past the intake manifold valves in a DI engine, but it won't do anything to clean or prevent carbon build up on the back of the valves. For that, you can do a Seafoam treatment, and if that doesn't work, you can get the intake valves blasted and cleaned with walnut media.
 
Last edited:
I've been keeping my eyes on the 2nd Gen CX-9 for quite some time. To me, reliability is something that I put into consideration as I usually like to keep a vehicle for a long time.

Any how, for those who have had their 2nd Gen CX-9's, how's it holding up? Anyone with 50,000+ miles on the vehicle yet? Any common issues to look out for? How's the transmission holding up? How's the engine(I've read about some people having issues with carbon build up, to be remedied by hard driving and/or some solvents into the intake valves) ?

The skyactiv Transmission is relatively new, and even more so the skyactive turbo 2.5 liter debut with the 2nd Gen CX-9. I was wondering how it looks after roughly 3 years.

TIA.
Same boat as you! Really interested in the CX9. I want my next vehicle to last 8-10 years. Never owned a mazda but I was a huge Pontiac fan when I was younger and I consider Mazda the sporty Japanese Brand. Idk I'm weird. But I love mazdas appeal. So I've been shopping 3 row SUVs for a while, narrowed it down to the Kia Telluride, Honda Passport(only 2 row but large cargo space) and the CX9. I'm looking at the 2019 CX9 Touring with AWD. I have the same concerns as you. Next owned a turbo engine before, Mazda does seem like theyve been using the same 6 speed tranny for a while and in all their cars. Not sure if its the same one. Heard some paint stories I'm concerned about. Tho the sporty and luxary that the cx9 offers kinda has me super intrigued. Ive test driven it 3 times and I love how it drives. We are also a bit concerned it might not have the size of the others we are looking at but it might be a good trade off for the sportiness and fun to drive nature.
 
I threw this question out a bit ago and had a few responses over 60-70k miles with no powertrain issues. The N/A version of this Skyactiv 2.5 had been basically bullet proof from what I read on the early CX-5's and others. Some of those are over 150k miles at this point. I think the carbon build up thing is overblown in general and Mazda has some technology in there to combat it. I think if you run good gas in it most of the time and run an additive through there every 10k miles it should not be an issue.
Wondering how much is different on the N/A Skyactiv 2.5 turbo that's in the CX9. I watched a video from Savagegeese on the CX9 and he said since the blowby is so fast on the Turbo 2.5 carbon buildup is virtually non existent.
 
:
2005 Mazda3
Same boat as you! Really interested in the CX9. I want my next vehicle to last 8-10 years. Never owned a mazda but I was a huge Pontiac fan when I was younger and I consider Mazda the sporty Japanese Brand. Idk I'm weird. But I love mazdas appeal. So I've been shopping 3 row SUVs for a while, narrowed it down to the Kia Telluride, Honda Passport(only 2 row but large cargo space) and the CX9. I'm looking at the 2019 CX9 Touring with AWD. I have the same concerns as you. Next owned a turbo engine before, Mazda does seem like theyve been using the same 6 speed tranny for a while and in all their cars. Not sure if its the same one. Heard some paint stories I'm concerned about. Tho the sporty and luxary that the cx9 offers kinda has me super intrigued. Ive test driven it 3 times and I love how it drives. We are also a bit concerned it might not have the size of the others we are looking at but it might be a good trade off for the sportiness and fun to drive nature.
I've had a lot of experience with Mazda and still drive my 2005 Mazda3. They can certainly be reliable cars, but they do take risks sometimes(releasing fairly new technology, like the skyactiv line, and the skyactiv-X, innovative but "risky" since it's so new and uncommon). Mazda seems to be serious about bettering their products each generation and particularly in "luxury", hence we get more sound deadening material and better interior quality each year, Mazda's definitely had some less robust paint protection compared to say Toyota(I've had some Toyota's and I can see where they reinforced wheel wells and underbody with more coating to give it better rust protection).

I'm compelled to Mazda again because of brand loyalty I guess you could say, no automaker is perfect but Mazda gets certain things right that I like. Kia has really upped their game lately and I admit the Telluride is very impressive, has the best cargo space inside(unfortunately the CX-9 has the smallest in it's class,which is a bummer to me but still forgivable), a more updated interior(lots more USB ports, a better infotainment, etc.), better towing(5000lbs vs CX9's 3500), a serious AWD system(it has a locking rear differential under 40mph which simulates 4WD), and a 3.8 Liter V6. The Telluride got my attention, but having said that, I'd still consider the CX-9 as it's been out a bit longer, and I care about reliability.

The 2nd gen CX-9 has the turbo(more moving parts, more factors, etc.... the 2.3 DISI in the cx-7 and speed3 was not what I would call a "bulletproof" motor, but it wasn't horrible either), plus I was concerned about the transmission due to the added vehicle weight and power output from the engine(more stress on the transmission compared to a CX-5/mazda6 etc... you would hope that they scaled the transmission up properly, but you never know.... I can use the MZR 2.0 to MZR 2.3 liter engine as an example, Mazda scaled certain components while leaving some components the same...down the road we later see that the MZR 2.3 liter was not as robust or reliable as the 2.0, which Mazda caught on and came up with the MZR 2.5l which was completely scaled up and didn't share a single component).

Glad to hear that people are reaching past 50k miles without much drama thus far... any engine hesitation at least? I saw interviews with Dave Coleman on how Mazda mitigated carbon buildup by trying to control engine temperature as well as other variables to "reduce" build up, but it's still prone to it, it may be better than some other Direct Injected motors, but not as fool proof as Toyota's solution: dual injectors... many other companies are following this solution as well, even Kia/Hyundai announced their new Direct Injection motors will be getting both port and direction injection in order to spray the valves clean for preventative measures.
 
:
2005 Mazda3
Wondering how much is different on the N/A Skyactiv 2.5 turbo that's in the CX9. I watched a video from Savagegeese on the CX9 and he said since the blowby is so fast on the Turbo 2.5 carbon buildup is virtually non existent.
The Turbo has several additional components and setups from the N/A version, including but not limited to the cooled EGR, the turbo itself, and one that especially caught my attention was Mazda's dynamic pressure intake valve. One of the first things I thought about was... "can it be easily serviced/replaced/cleaned if needed be", since it's one extra moving part and since it's an intake, stuff can gunk up in there. I guess we'll have to wait and see how the dynamic pressure intake actuators hold up 10 years down the road, but glad to hear they haven't had much problems within 3 years. Power delivery and tuning is another aspect between the N/A and turbo version, the N/A version is very linear in it's power delivery, whereas the turbo version gets a lot of power at the low end, so hopefully Mazda beefed up all the necessary components enough to handle the stress down the road, thus far it's probably safe to assume that they did.. I was more concerned with the transmission being able to handle the power for the long run.
 
:
2005 Mazda3
Wanted to resurrect this thread as it's been almost a year and there's surely more members who are above 50,000+++ miles.

I saw that some members have since had coolant leaks on the 2nd generation Cx-9:



User mchu123 states that he has 80,000 miles on his 2nd gen.

Anyone else racking up miles and have things to share?
 
:
Mazda CX-9 Grand Touring 2016
My 2016 only has 40k miles, but....not one problem.

Carbon on the backsides of the intake valves appears to have been solved by better trapping of the oil vapors in the positive crankcase ventilation system. Combustion gases leak by the piston rings...that's blowby. These get into the crankcase and have to go somewhere. Years ago they were just vented into the atmosphere. Then positive crankcase ventilation (PCV) was invented to vent the vapors into the intake manifold and reburn them in the combustion chamber. OK as long as gasoline mist from a carburetor or injection from a throttle body system or intake manifold system washed the oil mist off the valves. Gasoline direct injection (GDI) doesn't wash the valve heads, and early systems had the carbon problem. Improved trapping of the oil vapors inside the engine cured that. Gen. 2 CX-9 drivers who installed catch cans in the PCV system have yet to report any oil caught, as far as I've seen.

Turbochargers...I drove my 1996 Volvo turbo for 202,000 miles with the original turbocharger, and it was still good when I sold the car. Synthetic oil is not required in most, but it might be a help due to the heat. Allowing the engine to idle for a minute or two after a hot run (like at a highway rest area where one stops right after a long hot drive) is a good idea to allow the heat in the turbocharger to dissipate into the coolant and the flowing oil. Mazda makes no recommendations about alternate oil viscosities in extreme ambient temperature areas, but I'd run European-sped 5W-40 oil in Phoenix summers and 0W-20 oil in frigid winters. The oil needs to flow and protect the turbocharger.

I've heard no reports of transmission problems. It is always a good idea to filter hydraulic oil, and the in-line transmission filters like a Magnefine or Filtran in the hot line to the cooler can't hurt and will likely help extend transmission life.
 
:
2005 Mazda3
My 2016 only has 40k miles, but....not one problem.

Carbon on the backsides of the intake valves appears to have been solved by better trapping of the oil vapors in the positive crankcase ventilation system. Combustion gases leak by the piston rings...that's blowby. These get into the crankcase and have to go somewhere. Years ago they were just vented into the atmosphere. Then positive crankcase ventilation (PCV) was invented to vent the vapors into the intake manifold and reburn them in the combustion chamber. OK as long as gasoline mist from a carburetor or injection from a throttle body system or intake manifold system washed the oil mist off the valves. Gasoline direct injection (GDI) doesn't wash the valve heads, and early systems had the carbon problem. Improved trapping of the oil vapors inside the engine cured that. Gen. 2 CX-9 drivers who installed catch cans in the PCV system have yet to report any oil caught, as far as I've seen.

Turbochargers...I drove my 1996 Volvo turbo for 202,000 miles with the original turbocharger, and it was still good when I sold the car. Synthetic oil is not required in most, but it might be a help due to the heat. Allowing the engine to idle for a minute or two after a hot run (like at a highway rest area where one stops right after a long hot drive) is a good idea to allow the heat in the turbocharger to dissipate into the coolant and the flowing oil. Mazda makes no recommendations about alternate oil viscosities in extreme ambient temperature areas, but I'd run European-sped 5W-40 oil in Phoenix summers and 0W-20 oil in frigid winters. The oil needs to flow and protect the turbocharger.

I've heard no reports of transmission problems. It is always a good idea to filter hydraulic oil, and the in-line transmission filters like a Magnefine or Filtran in the hot line to the cooler can't hurt and will likely help extend transmission life.
PTguy, out of curiosity, did you install a oil catch can on your Gen. 2 CX-9?
 
"Mazda makes no recommendations about alternate oil viscosities in extreme ambient temperature areas, but I'd run European-sped 5W-40 oil in Phoenix summers and 0W-20 oil in frigid winters. The oil needs to flow and protect the turbocharger."

I know I may start an argument here, but I disagree with the recommendation to change oil specs from the manufacturer recommendations. Especially when it comes to the last digit of the oil (ie. the 20 in 0W-20). That last digit is the viscosity of the oil at high temperature (210F). This is the indicator of the oil viscosity at engine running temperature (once your engine is hot), regardless of exterior temperature. So if you go with xW-20 instead of xW-30, once your engine is at its operating temperature your oil viscosity won't be right (which is most of the time unless you have a very short commute). I am sure there are a lots of canadian folks (including myself) that can tell you that there are no issues with the recommended 5w-30 in northern climate unless maybe if you start going into the northern territories.

Following the same logic, in warm climate, going with a 40 grade oil instead of 30 only make sense if your engine is running warmer than its normal operating temperature (and even then there are a lot of unknown variables which we are making assumptions of here). If when you are driving your engine temperature gage remain within normal operating limit (thanks to the cooling system), then again you are now running the wrong viscosity of oil in your engine, and potentially causing more harm than good.

It is a bit different with the first digit, the first digit is the viscosity at cold temperature, so changing the first number (example, 0W-30 instead of 5w-30) sometime can be useful to help for cold start and during engine warm up. That would be the only number that i would consider playing with for cold climate conditions, because it doesn't affect the viscosity at high temperature (normal engine operation).

Mazda oil specs for North America are 5W-30 (Mexico to Canada), I can't claim to be living in conditions colder than Canada/Alaska or warmer than Mexico. Mazda specs are a bit more lenient in Europe where they say 5W-30 or 0W-30 and 10W-30 can be used (notice how the 30 doesn't change), but we don't know what other factor, if any, may be different in the European engine compared to North American engine.
 

Montanaman

Montana/Arizona
:
2018.5 CX-9 AWD GT
Wondering how much is different on the N/A Skyactiv 2.5 turbo that's in the CX9. I watched a video from Savagegeese on the CX9 and he said since the blowby is so fast on the Turbo 2.5 carbon buildup is virtually non existent.
I saw the same video and it looks like Coleman and company tried to mitigate this carbon issue and maybe they did. We will need to see somebody who has their injectors looked at with 50k miles or so on them.

Meanwhile it is an issue with Honda's " Earth Dreams" V6 that is in many vehicles including my 2019 Ridgeline and these are not turbo charged engines. Reports of clogged injectors due to carbon build up and Honda changed the injectors going forward so we will see. It appears that Toyota's dual port is a good idea.
 
:
Mazda CX-9 Grand Touring 2016
Youri, the one point I'd like to discuss is the concept of "engine temperature." What we get as engine temperature is one measuring point, the coolant outlet of the head. That's what the thermostat controls, and that's what is displayed. There are many other temperatures inside an engine that are only measured on large engines or on test engines. Oil temperature has only a moderately close relationship to coolant temperature. The temperature of the oil in the sump, in the crankshaft bearings, in the head, and in the turbocharger bearings will vary greatly partly depending on the ambient temperature as well as how hard the car is driven or how much weight it carries. The oil in the sump after the coolant reaches operating temperature, for example, will be much lower in a cold winter night than it will be in a hot Death Valley day. I've operated very large diesel engines where there were multiple oil temperature thermometers and sensors. Each main bearing, each con rod bearing (catch pans in the crankcase with sensors caught the splash from the bearing), crossheads (similar to a wrist pin), outlet of each turbocharger, inlet & outlet of the cooler all were measured. Each one was different.

I drove our 1996 Volvo 850 turbocharged engine for 200,000 miles, original turbo running fine, and that specified 5W-30 for normal temperatures and 5W-40 for operation in air temps mainly above 90°F. That engine had the oil cooler inside the hot tank of the radiator so the oil was cooled by the 195° hot coolant from the engine (the transmission fluid cooler was inside the radiator cold tank); the oil to the cooler was controlled by a thermostatic valve.

We want the oil to be the proper operating viscosity when it is normally warm, maybe something like 220°F. In frigid winter weather the oil is unlikely to get that warm, so a lower viscosity labeled oil, 0W-20 or 5W-20 for our engines, will do well. In blistering summer heat (Phoenix), a 5W-40 oil is more likely to give the correct operating viscosity when the pavement is hot enough to burn skin, and the engine is just a few inches above that pavement. I no longer drive in frigid winters (I was in Wyoming with -50°F nights and -25°F sunny days years ago), and I don't drive in scorching southwest areas. 5W-30 works for me.

Do our Mazda turbo engines have an oil cooler (I haven't seen one)? Oil is cooled by heat transfer through the engine metal to the coolant, by air flowing past the outside of the block, and by air flowing past the sump. Grill shutters, electric fan, and the belly pan change that, and the brilliant Mazda engineers, Sky-san and Activ-san, have allowed for that.
 
PTGuy, good discussion point. You bring up a good point that we don't have the actual value of the oil temperature (we only see the coolant temperature), and that it varies throughout the engine in different location. And yes you are correct when you say the oil is likely to run be warmer throughout at engine operating temperature in warm exterior temp than in cold temperature (because of how much it cools through the pan, lines, etc). If the car can keep its coolant temperature within operating limit, it is likely that the oil temperature is within specs, even if it is warmer than it would be normally on a cool day.

That being said, my opinion is that we don't know by how much it varies, and it depends on the cooling system design to a degree. When you drive this engine in phoenix, the oil is generally warmer than in cooler climate, but is it too thin for the specific areas where it matters? and is 5W-40 the right viscosity ? It is the next available step up, but is the difference in oil temperature enough to bring the 5w-40 to the same viscosity as the 5w-30 for the engine ? How much of a temperature difference is required to have a 5w-40 at X degree F act as a 5W-30 at 210F ?

Engine engineers go through the headache of determining the best oil viscosity for a wide range of conditions. In theory they did their homework and got it right. It is very likely that for conditions of constant high temperature or constant cold temperature, there may be a better grade than 5w-30 for this engine, but unless it is in the service manual or someone worked on the design of this engine, it is impossible to know for sure. So by deciding to use a different grade, we pretty much take a stab in the dark, and also end up running the wrong oil when the conditions are not as extreme (evening and mornings in phoenix for example). You may have success with it, or you may not. Nobody can tell.

To sum it up, the concept of changing the oil type based on various conditions make sense on a viscosity only basis, but unfortunately I don't think we know enough in most cases to make that decision.

I don't know if our engine has an oil-cooler. I think it has one for the automatic transmission oil (2 x in europe), but I don't know for the engine oil.
 
I've been keeping my eyes on the 2nd Gen CX-9 for quite some time. To me, reliability is something that I put into consideration as I usually like to keep a vehicle for a long time.

Any how, for those who have had their 2nd Gen CX-9's, how's it holding up? Anyone with 80,000+ miles on the vehicle yet?


Any common issues to look out for? How's the transmission holding up? How's the engine(I've read about some people having issues with carbon build up, to be remedied by hard driving and/or some solvents into the intake valves) ?

*New: Any coolant leaks observed? (we've had a few members on here who had coolant leaks which resulted in needing a brand new engine, would be nice to get more feed back on the community from higher mileage 2nd gen's and see how your engines are holding up)

The skyactiv Transmission is relatively new(CX-5 seemed to have some problems after about 50k miles), and even more so the skyactive turbo 2.5 liter debut with the 2nd Gen CX-9. I was wondering how it looks after roughly 4 years.

TIA.
So I got a 2019 Touring with just over 26k miles. Spirited road-trips to Yosemite, San Fran, daily 2 hour Los Angeles commutes on surface streets and busy freeways. Car still feels as fresh as the day I got it; nearly flawless. Couple mentions however: I bring my own full synthetic 5-W30 to every dealer oil change, at no more than 6k intervals (book says 7500 (did the first one at 5k cause I’m nervous about owning my first turbo engine). It once consumed 1 whole qt around at 5k interval and I immediately topped it off and took her in. Lastly, had a clunking sound develop on the front passenger corner at 20k miles when depressing the brake after parking it. Turns out there was a CX5 service bulletin for a brake caliper component that allowed it to get loose. They applied the 5 bulletin to my Cx9 and replaced under warranty. Issue has not resurfaced. Knocking on wood, but thrilled with the quality so far (Former multiple Honda owner).
 
:
2018 Mazda CX-9 GT
I've got a 2018. It's got 40K miles on the clock now. It was put into service exactly two years ago; June 2018.

To give you an idea of the type of driving that this SUV gets, I live in Washington DC. This car gets well over the regional average of 12-15K miles per year put on it. I drive hard and aggressively; I got my first triple digit speeding ticket in the CX-9.

I have fun with the CX-9:

I tow with the CX-9:

It has moved me between two houses and my mother-in-law between two houses.
I have two kids, aged 6 and 8. It ferries them to various activities and to school.
My wife works in community mental health and uses it daily to get to and from appointments in city driving.

This SUV gets used for SUV like tasks.
I do not usually use Premium 93 AKI fuel, I use Regular old 87 AKI fuel.

The oil gets changed every 5000 miles. 30K miles and below were all done at the dealership.
Air and Cabin air filers were done at 30K miles.
I did the 35 and 40Kmile oil changes and will be doing all subsequent maintenance.

I also did brakes all around at 40K. The rear brake pads were at the wear limits. The fronts still had life left in them, but I upgraded from the factory pads (ADVICS) to PowerStop brake pads and did both ends.

I will be getting tires before winter as the factory Bridgestone Ecopia 422s are at the end of their life. I'm leaning towards Michelin Defender LTX highway tread tires, as this SUV doesn't see much deep sand or mud. The tire gets good reviews on TireRack.com

Maintenance Schedule says the plugs should be done at 40K miles. I have not inspected the spark plugs, but mileage hasn't taken a hit. Unfortunately, everyone's out of stock of the specified NGK Stock Number 90288 (Part number DILKAR7M8) plugs. I will probably do them shortly.

So 20K miles a year means I'm doing maintenance quarterly. I have not noted anything deficient mechanically. All fluids are within specified ranges and there are no leaks.

I will probably have the transmission fluid, rear differential gear oil, and transfer case oils changed out at about 50K miles, despite being ahead of schedule... Just due to the heavy use I put on the SUV.

Cosmetically, I have noted that the paint gets blemishes quickly. Even on it's first detailing when I applied the protective paint coating, I noted tons of orange peeling, rock chips, and dings in the paint. This is consistent with various internet reports on the 46V Soul Crystal Red being applied very thin and prone to damage.
 
:
Mazda CX-9 Grand Touring 2016
I don't think NGK distributes their DILKAR7M8 plugs in North America. I got mine from a dealer and put them in at 40k. Improved pep. Do it. It takes an assortment of 8mm & 10 mm sockets & end wrenches to loosen the plate that holds several relays and other gizmos that sits above the plugs. The spark plug socket is a 14mm...one more new tool added to my box.
 
Top