2.5 NA Cracked Cylinder Head with Oil leaking...How common is this?

2020 MAZDA 3 2.5L 2488 CC L4 16 VALVE AWD
hairline crack in cylinder head 47,000 miles.
I had mechanic take a look and we took a video of problem.
Currently at Mazda dealership awaiting call from them.


 
2020 MAZDA 3 2.5L 2488 CC L4 16 VALVE AWD
hairline crack in cylinder head 47,000 miles.
I had mechanic take a look and we took a video of problem.
Currently at Mazda dealership awaiting call from them.


Thanks for the report. Hope Mazda North American Operations will replace the cylinder head under powertrain warranty soon.
 
Mazda probably did not reinforce the engine block from NA to Turbo.
Now they do with latest change.
These aluminum engine block was casted, not forged...
This cracked cylinder head issue is for 2.5L NA with cylinder deactivation. I want to emphasize that the cylinder head on the 2.5L NA with cylinder deactivation is different from the one on the 2.5L NA without CD. Mazda apparently modified the cylinder head based on the previous head to accommodate switchable hydraulic lash adjusters used only for cylinder deactivation, somehow weakened now the cracked area on the cylinder head. It’s another inherited problem from CD now gets exposed.
 
Thanks for the report. Hope Mazda North American Operations will replace the cylinder head under powertrain warranty soon.
Just got mine back on Saturday. Was out of
This cracked cylinder head issue is for 2.5L NA with cylinder deactivation. I want to emphasize that the cylinder head on the 2.5L NA with cylinder deactivation is different from the one on the 2.5L NA without CD. Mazda apparently modified the cylinder head based on the previous head to accommodate switchable hydraulic lash adjusters used only for cylinder deactivation, somehow weakened now the cracked area on the cylinder head. It’s another inherited problem from CD now gets exposed.
I really wish they never added CD to any of the 3s. It was removed on the ‘21 models because I’m sure they aware it’s problematic tech! Hard lesson learned, I knew better.
 
me too, good thing i caught the leak this morning on my way to work. thanks for the info. i will keep everyone updated as i get updated
You and I both. Noticed it one Friday after work, had it at the dealership the next morning. Everything was covered under warranty luckily. I like my car but I’ve lost faith in keeping it after the warranty expires.
 
Just got mine back on Saturday. Was out of

I really wish they never added CD to any of the 3s. It was removed on the ‘21 models because I’m sure they aware it’s problematic tech! Hard lesson learned, I knew better.
Glad you got your Mazda3 back after 2 months of out of service.

Didn’t aware Mazda had dropped the cylinder deactivation feature from the 2021 Mazda3. Hope Mazda will do the same to the CX-5 very soon.
 
You and I both. Noticed it one Friday after work, had it at the dealership the next morning. Everything was covered under warranty luckily. I like my car but I’ve lost faith in keeping it after the warranty expires.
trust me i might do the same after my 60k expire, this is the 2nd time going in for work, my digital gauge cluster lost a row of pixels a few moths back, now this..
 
Just got mine back on Saturday. Was out of

I really wish they never added CD to any of the 3s. It was removed on the ‘21 models because I’m sure they aware it’s problematic tech! Hard lesson learned, I knew better.
Everything I've seen shows the 2021 CX5 2.5 regular engine as still having cylinder deactivation.
 
Everything I've seen shows the 2021 CX5 2.5 regular engine as still having cylinder deactivation.
Yes, he said only the 2.5L NA in Mazda3 has dropped the cylinder deactivation since 2021 MY.
 
12.22.2021


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**UPDATE** After 7 weeks of waiting i finally have my car back, everything was covered by Powertrain warranty and they also provided me with a loaner. I also received a refund of $90 that my local mechanic charged me to diagnose the problem before i brought it to the Mazda dealership, I just contacted Mazda corperate and they worked with me to get my money back. Overall they did the right thing and fixed my cracked head. The only thing that bothers me is if this happens to anyone that has an expired Power train warranty they will be responsible for a hefty bill.
 
**UPDATE** After 7 weeks of waiting i finally have my car back, everything was covered by Powertrain warranty and they also provided me with a loaner. I also received a refund of $90 that my local mechanic charged me to diagnose the problem before i brought it to the Mazda dealership, I just contacted Mazda corperate and they worked with me to get my money back. Overall they did the right thing and fixed my cracked head. The only thing that bothers me is if this happens to anyone that has an expired Power train warranty they will be responsible for a hefty bill.

Still waiting on the replacement head for my CX5. :(
Glad your car's back to "normal" and hopefully this will not be a recurring issue.
 
**UPDATE** After 7 weeks of waiting i finally have my car back, everything was covered by Powertrain warranty and they also provided me with a loaner. I also received a refund of $90 that my local mechanic charged me to diagnose the problem before i brought it to the Mazda dealership, I just contacted Mazda corperate and they worked with me to get my money back. Overall they did the right thing and fixed my cracked head. The only thing that bothers me is if this happens to anyone that has an expired Power train warranty they will be responsible for a hefty bill.
So that leads to a question....is anyone considering selling their CX5 at the end of their powertrain warranty to avoid the risk of getting stuck with the cost of this repair????
 
So that leads to a question....is anyone considering selling their CX5 at the end of their powertrain warranty to avoid the risk of getting stuck with the cost of this repair????
I'm still debating it, but i can tell you this i WILL be looking at other cars, and if i get a decent amount for my Mazda 3 and i find another vehicle for a good price then I'm jumping on it.
 
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