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

57k on my 2017 signature.. went to the dealer for an oil change, ran over something that absolutely shredded my rear tire, was headed to Orlando for the weekend, so I had the dealership put a new tire on... best move ever... they had it up to put the tire on, they noticed a coolant leak. Now they are ordering a new engine under warranty. Just happened yesterday, so I'll go get more info after my trip, at least I was already in a loaner cx-9.
 
I guess Mazda replaced the water pump failure mode with another mysterious cooling system flaw.
 
57k on my 2017 signature.. went to the dealer for an oil change, ran over something that absolutely shredded my rear tire, was headed to Orlando for the weekend, so I had the dealership put a new tire on... best move ever... they had it up to put the tire on, they noticed a coolant leak. Now they are ordering a new engine under warranty. Just happened yesterday, so I'll go get more info after my trip, at least I was already in a loaner cx-9.
Thanks for sharing your experience, as these 2nd gen cx-9's age we are seeing more and more of these "coolant leak" issues, followed by a full "engine replacement", hopefully it's still a more isolated issue rather than being common. It's fortunate that your problem showed up just before the warranty expired! It's my understanding that Mazda has a new part number for the engine block on the 2.5 turbo's starting 2020(I believe?)... hopefully they figured it out and the cracked/leaky engine blocks won't be an issue going forward.

If I consider a used one in the future, I'll definitely consider getting an extended power train warranty.
 
Thanks for sharing your experience, as these 2nd gen cx-9's age we are seeing more and more of these "coolant leak" issues, followed by a full "engine replacement", hopefully it's still a more isolated issue rather than being common. It's fortunate that your problem showed up just before the warranty expired! It's my understanding that Mazda has a new part number for the engine block on the 2.5 turbo's starting 2020(I believe?)... hopefully they figured it out and the cracked/leaky engine blocks won't be an issue going forward.

If I consider a used one in the future, I'll definitely consider getting an extended power train warranty.
I'll get more info Wednesday on what exactly they are doing. Shredded tire, I'm surprised it didn't blow... I hit whatever did this about 3/4 mile from the dealership and it drove fine. Bridgestone duellers must have very stiff sidewalls!
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Wow, that is a massive cut. Can I ask what you hit?
no idea, I was in the right lane on a 6 lane road, and police car to my left, so I glanced over at him and that was the moment i ran over whatever was in the road... I think it was something flat that I ran over and my front tire kicked it up at just the right angle for my rear tire to run over.
 
failed cylinder head was the cause, I'm still waiting for the full writeup.

the master ase who was doing the tire change was checking the vehicle, noticed the coolant was low, went to fill it, and it didn't fill up the coolant, so he deduced it was going somewhere else, he checked the oil and the coolant was mixing into the oil.

I'm still in a loaner vehicle, pickup is supposed to be tomorrow or friday, when I'll get all the paperwork.
 
Interesting. The more info you can get about what's going on with these engine failures the better. Cylinder heads often fail due to other failures, like a head gasket failure or other deficincies in the cooling system. Keep us posted, and thanks for posting here.
 
On the bright side, I was just about to pay for a power steering flush and coolant flush, and it was actually in to have the spark plugs swapped along with oil change, so I got those for free. So I got a whole list of service stuff done for free. Now I'm just wondering do I trade this in on something else, or hope that the repair holds. No warranty on the repair other than the 60k warranty which i'm 3k from being finished with.
 
Yes, looked it up, but I can't find a description of what that entails. How partial an engine is that? Looks like they did the differential fluid, transmission fluid too. Scares me when I see all those gaskets and seals... if one of those is put in wrong, it's just a problem waiting...
Well, I checked most of those gaskets, none of them is a head gasket, so it looks like it's the full engine to me. I too am curious as to what partial engine means, unless a full engine means engine + turbo + transmission + all other bolted on stuff as well.
 
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From the looks of the list, they had to remove the exhaust manifold and turbo from your old engine and swap it to the new one, along with the intake manifold, EGR valve, and parts of the cooling system. When they removed the exhaust manifold they had to replace all the exhaust gaskets between the turbo and exhaust manifold and the rest of the exhaust system as well.

There was someone else on here that had problems after buying an engine swapped CX-9 because one of the wiring harnesses was damaged.
 
From the looks of the list, they had to remove the exhaust manifold and turbo from your old engine and swap it to the new one, along with the intake manifold, EGR valve, and parts of the cooling system. When they removed the exhaust manifold they had to replace all the exhaust gaskets between the turbo and exhaust manifold and the rest of the exhaust system as well.

There was someone else on here that had problems after buying an engine swapped CX-9 because one of the wiring harnesses was damaged.
Yeah, trust me, I'm gonna go over it with a fine tooth comb and I have a friend with a lift, I'll probably lift it and check underneath also. Altho, the dealer has promised me they will take care of it if the car has an issue in a few months. The dealer does seem to be one of the better ones.
 
The few threads on the engine replacement cases for 2016/17 are getting me to lose confidence on the CX9 reliability. I was planning to keep the CX9 for a long time now I may look into the extended powertrain warranty.
 
Coolant leaks necessitating an engine block replacement?!
Great... Now y'all got me nervous.

55K on the clock. I did the Spark Plugs at 50K. They didn't look that bad.
Just had the trans and differential serviced.
And I did brakes... Again. Just reviewed the pads I pulled off of it.

 
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