Which parts fail
Components named in complaints (automatic and manual transmissions, CVT, axles, driveshaft, 4WD/AWD).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2011 Mazda CX-9 owners, lightly cleaned up (personal details are redacted by NHTSA).
I had an issue with the AWD not engaging and the 4x4 light illuminating when driving on snow and ice. No indicators when driving under normal conditions. I had no traction and had difficulty maintaining control of the vehicle while driving at speeds less than 25 mph. I had difficulty gettting momentum from a stop as the tires were spinning and engaging tracion. I took the car into a Mazda dealership for a full circle inspection and found that the 4x4 light was illuminating due to worn-out splines connecting the transfer case. The technician was able to spin the driveshaft, indicating the splines are damaged and need to be replaced. Recommendations were to replace the transmission and transfer case with a repair estimate of $5469.61. …
The front driver-side lower ball joint suffered a catastrophic structural failure and sheared completely apart while moving. This vehicle was previously serviced under Safety Recall Campaign 15V451000 / Mazda Recall 8515G for this exact defect. The recall remedy part failed a second time, collapsing the front wheel assembly, ripping the CV axle completely out of the transmission casing, causing a hazardous transmission fluid spill, and leaving the vehicle stranded and immobilized in the middle of a live roadway in the dark
When getting off highway engine began to knock. Engine stalled and would not restart. Upon inspection the water pump was found to have failed and leaked engine coolant into oil. This caused engine to have a complete failure. No check engine light illuminated but when car was scanned multiple codes were found. The car was also found to have a bad Transfer Case.
The Mazda 2011 CX-9 crossover SUV seems to have a defect in the power transfer unit (ptu). Mazda north American operations issued a letter to Mazda owners informing about a special service program to extend the warranty coverage for the repair of the power transfer unit (ptu) on "certain 2010-2011 CX-9 all-wheel drive vehicles produced from July 28, 2009 through December 2, 2013." I quote the letter. On March 18, 2015, I began to experience a problem whereby my 2011 CX-9 made a grinding and snapping sound when in reverse mode. This behavior was followed by a pungent odor in the cabin. I contacted the nearest dealership and tried to get an immediate appointment to examine the vehicle. However the dealership could not accommodate me nor expressed any awareness of the symptoms. Yet, the letter was published since last year. …
I was driving my 2011 Mazda CX-9 and the car was smelling like it was burning and then it sounded like a pile of rocks being tossed around I pulled over to the side of the road and something exploded the car came to an abrupt stop and smoke came from underneath the hood. I had it towed to a repair shop and was told the transfer case went out and messed up the transmission. After doing research on the internet I found out this is a common problem that Mazda has known about for some time and has failed to notify the customer. This problem has apparently caused vehicles to catch fire while driving. After contacting Mazda they say they extended the warranty to 90,000 miles because of this problem but hasn't notified the owners of the vehicle. …
While driving the car on a county road, with the speed under 40 MPH, and following the bend in the road to lead to getting on the highway, the car jerked forward as if I hit something. As I continued to drive, the car was making loud clinking sounds and was jerking in motion. No warning lights went on. While attempting to continue to drive, clanging noises could be heard and the car continued to jerk forward. The car was unable to be driven. After having it towed to my mechanic, it was determine the problem was the transfer case. The splines between the transmission and transfer case had been eaten away by rust. The seal had not kept water out as it was designed to do. A new transfer case was ordered as well as a new transmission. The replacement transfer case had shown signs of the same issues with the splines. Another (2nd one) transfer case had to be ordered. …
My power train was supposed to be covered to 100,000 miles. When the tranfer case had to be replaced as per warning it happened at 93000 onstead of 90000 but I was told that not only eas I not covered but that the supposed warranty covered to 100000 miles was not valid either because the car wasn't classified at Mazda as a certified pre-owned car and the only reason I bought the car was although the mileage was high,approximately 54,300 miles for a 2 yr.old car I purchased it because with it supposedly being pre-owned car, the power train was to be warranteed to 100000 miles so picture my shock whrn I was told that the car was not considered to be pre-owned and that the power trsin wouldn't be covered. I must take it up with the dealer. So I was stick with the payment of the replacement of a part that was listed for recall. …
The transfer case in our 2011 Mazda CX-9 failed at 130,000 miles. I understand that Mazda know about a defect as to the proximity of the transfer case to the exhaust. The heated transfer case lubricant become sludge-like and causes the case to fail also affecting the transmission splines. The heated lubricant escaped and drips on the exhaust and fills the vehicle with a toxic smelling gas and apparently can light on fire. The transfer case failed while driving making getting out of traffic difficult. Mazda issued a bulletin in 2014 extending the warranty to 7 years or 90,000 miles but didn't inform any of the customers of this problem. There is no service schedule for the transfer case as recommended by Mazda. Or any way I understand to change the lubricant in the transfer case. …
Traveling with family on i95 started smelling a burning odor. Later developed a distinct vibration and grinding sound. Got it home now non usable. Vehicle was previously repaired at my shop , a loss due to hurricane sandy, and as such branded. Faulkner Mazda and Mazda corporation both denied any warranty claim due to title branding even though both admitted it was a safety issue , although the service dept at faulkner did add "that anything could cause an accident". I am just lucky that it didn't grenade while on the interstate at speed with my family in the car. Corporate Mazda advised me to save my receipts in case they issue a recall in the future. Will not recommend Mazda to anyone in the future.
Tl* the contact owns a 2011 Mazda CX-9. The contact stated that while driving at 70 MPH, a strong odor of fuel fumes was inside the vehicle and an abnormal noise could be heard from the front of the vehicle. The vehicle was taken to an independent mechanic where it was diagnosed that the transfer case needed replacement but the repairs were not completed. The contact then took the vehicle to a dealer where the failure was then confirmed. The manufacturer was notified of the failure. The failure mileage was approximately 103,000.
Transmission complaints in other CX-9 years
Frequently asked questions
How common are transmission problems on the 2011 Mazda CX-9?
NHTSA has 25 complaints about the transmission & drivetrain of the 2011 Mazda CX-9, 15% of the model year's 170 complaints. The component named most often is transfer case (4-wheel drive) (1 mentions).
Is there a recall for 2011 Mazda CX-9 transmission problems?
No. NHTSA lists no transmission & drivetrain recall for the 2011 Mazda CX-9, though it has 4 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2011 Mazda CX-9 transmission problems start?
Half of the complaints with a recorded mileage happened before about 87,000 miles, and 5% before 25,000 miles.
Is it dangerous?
Owners linked 0 crashes, 1 fire and 0 injuries to transmission & drivetrain problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.