Most things produced by Mazda in recent years have being fantastic. The CX9 is no exception to this. The common issues with these seem to be smashing through tyres, water pump leaks and looking like you don’t know how big your car is whilst parking. Aside from that they are spectacular vehicles. It should not come as any great surprise to you that the CX9 ranked very highly in our “best cars for Sydney mums” list. You can find that list by clicking the link here.
We have covered the water pump fault in a previous article which you can locate here.
One issue that does seem to be very common with the CX9 is the failure of the brake booster. For most drivers this is a mythical part made up to rob consumers of their hard earned money. Unfortunately this is not the case and the part is an essential component to its brake system, arguably the vehicles primary safety feature.
The boosters are known to fail internally. The result is the brake system no longer has vacuum assistance and the driver is now solely relying on mechanical braking. For most this means nothing, to you but when it happens to you, you will know something is wrong. The brake pedal becomes very, very heavy or hard to push. The brakes still work but you will need to stand on the brake pedal to get it to pull up.
If this ever happens to you it is advised to stop driving the vehicle, it is unsafe and the brakes are kind of important to basic motoring. Get your car towed and get it sorted.
Unfortunately this repair is not cheap. Secondhand is an option but be warned this is a rather common fault with the CX9, buying secondhand leaves you with a high risk of buying something with the same fault or worse. Genuine Mazda is really the only way to go. About to remove it is not much fun with the job taking several hours too.
You don’t have to replace the master cylinder whilst doing it however, if is already leaking out the rear seal or you are suspect that it is now the time to replace that too, as its going to have to be removed for this job regardless.