2016~2023 CX-9 DIY Cylinder head replacement (workshop/service manual)

Hey , all, just got the news my head gasket was blown (block test came back okay) from an independent shop.

After doing further research, we came across the cracked cylinder head TSB and have decided this is the issue instead due to vehicle production date.

I will be replacing the cylinder head myself and want to get some specs to complete the job, such as if there are any specialty tools needed to get the job done.

This will not be my first rodeo but will be my first cx9.

Has anyone checked out the Mazda service manual that is offered for 30$ -24 hours or 250$- 30 days?
Thanks for the response. Will definitely check this out. I also found a pdf for a service manual, that has all the torque specs.

Do you happen to know what driver/ socket the cylinder head bolts use ?

I have a poly driver for Audi/vw that looks similar to what might be needed
Although I did read that the 2.5t is a completely different/ redesigned engine compared to the 1st gen. Not sure if it’s applicable
Which year is your CX-9? Yes the 2.5t is totally different from the V6. None of it is applicable. So if you have a gen 1 with a V6 then the cracked cylinder head TSB for the 2.5t on the Gen 2 won’t apply.
In the link i sent above, the mazda CX-9 (TB) manual is for the 3.7l V6, and the CX-9 (TC) is for the 2.5T .
Really appreciate this! It’s a 17… so it’s the 2.5 turbo.

I come from an Audi background so I’m familiar with timing chains. (Ha) any way, I read the service manual that another member posted , which in fact might be the subscription manual from Mazda that someone bought and data logged, but going through it there really isn’t any type of specialty tools for the whole job. Which might be the case..
I will definitely shoot a message over to lucklyz.

I will also post my progress with the job !
After going back and forth to whether or not replacing the entire engine or just the heads, have decided to go ahead and only replace the cylinder head.
The parts have been ordered and will start the job this weekend. The cylinder head will not be here until next week, this gives the opportunity to order more parts if necessary and then finish the job next weekend…

Will be updating this thread with pics as the job progresses

Thanks to all that have helped thus far!
Here we go. Depending on how hard the turbo and other items are to remove, will be the deciding factor on whether the whole engine comes out or just the head.


  • 11FDCE32-ABB7-418F-8091-A3B958554840.jpeg
    176.1 KB · Views: 27
Ok so to use the service manual you have to use Microsoft edge browser or enable the function to view in a different browser.
I was using my iPhone originally and could not view it, I thought the link was dead and ended up wasting 30$ on the Mazda website , there was no service manual there anyway.

But like I said you first need to go to this link and switch the setting if you are not using Microsoft edge.

If you are using Microsoft edge here is the.m link for the manual. It is for the Australian cx5 but it is the same for the 2.5t cx9.

Here is the service manual… all the credit goes to @luklyz
He has paved the way and has provided so much info and help!

If your going to take on the job you need to start from the top of the motor and work your way down, then remove the windshield cowl strut bar and work your way down the backside of the motor removing the Downpipe. Also the passenger axle needs to be removed.

The plan is to remove the engine today.
Maybe there is a tech out there or a machinist that might be able to help identify a crack or the problem. I am having a hard time identifying if there is a crack in the head or if the head gasket was bad


  • 986798B9-6125-49FA-983D-03FE8A0877EE.jpeg
    134.7 KB · Views: 24
  • D9C948B6-E8F7-415F-BF28-57EACAB01887.jpeg
    145.6 KB · Views: 23
  • 5C3F0842-2DAA-42CC-A428-02DB9A8E9D3C.jpeg
    128.4 KB · Views: 22
  • E4648454-D3F5-45A1-A677-5FF50EE374D2.jpeg
    162.2 KB · Views: 24
  • 6516E71A-4996-4FF3-974D-4FE32D7923D1.jpeg
    164.5 KB · Views: 25
The TSB shows were the cracks would be and have a few example photos. Do you have it on hand?
I am out of town until Thursday. I will definitely take some more pictures. I’m also considering taking the head to a machinist or picking up some crack detection powder like they use to find it.
The head gasket does not look eroded enough to be the problem