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 2008 Mazda CX-9 owners, lightly cleaned up (personal details are redacted by NHTSA).
Vehicle is AWD. In May 2016, TCS & ABS dash lights came on as well as the depiction of a vehicle skidding. Brought to my local mechanic who said he was getting fault codes but could not diagnose. Suggested we go to the dealer. Went to local Mazda dealer who diagnosed that both the transfer case and transmission gears were stripped, that the vehicle was now operating in 2 wheel drive and that the ABS was not functioning because of these issues. Dealer quoted $8,136 to fix. We assumed there must be some recall on this issue but could not find one. We then brought to a local transmission expert who opened it up and described same problem. Stripped gears on both transmission and transfer case. He called dealership parts dept. And said they had several of the major parts he needed to repair. …
The power transfer unit (ptu), aka transfer case on my 2008 CX-9 broke, which subsequently destroyed a perfectly good transmission. The ptu is poorly designed and improperly fitted to the CX-9 and there are hundreds if not thousands of cases of the exact same problem in any Mazda user forum. My Mazda is only used for commuting and common street use. I noticed a toxic smell of burning transfer case oil on the exhaust, which filled the cabin. The rear wheels would no longer drive the car. Mazda has not recalled this part, and even worse they have used it in all AWD CX-9 models from 2007-2009. It is simply not designed to handle the weight and power of this vehicle, and is "sealed" from the factory with "lifetime oil" that breaks down over time. Mazda USA has extended the warranty of this part, noted in the ssp92 warranty extension. …
I was driving my 2008 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 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. Mazda says it hasn't been recalled because it isn't a safety issue (which I disagree with, it could cause great harm or death) and it hasn't been reported enough. …
When driving vehicle a severe shuddering vibration and loud noise emanated from front end of vehicle, as if front axel was going to fall off. Happened three times so far. Once to my wife, once to me, and once to the mechanic. Very frightening each time, causing drivers to pull over and turn off vehicle. Then vehicle drives OK for a while. Happened while driving straight forward. Mechanic states it is a failed power transfer unit. Mechanic's research indicated it is a big problem in Mazda CX-9 vehicles, and a class action lawsuit was filed and resulted in a settlement. As far as I can tell that settlement does not cover my vehicle year (2008), and is limited to vehicles manufactured after 2010, and which meet certain specifications. Mechanic estimates repair will run in the $1100-$1500 range. …
I was making a right turn from a parking lot onto a road with my two children in the car when a loud crunch happened, the vehicle jerked left while still moving forward and I was unable to steer or break. The car came to an abrupt stop and I couldn't get the driver's door open. I walked around to the front of the car while in traffic and noticed loose parts that had been ejected from the wheel, leaking break fluid, and the driver's side front wheel was no longer attached and had wedged under the car. The car was unable to be moved out of the road thus creating a traffic jam. The tow truck driver said the control arm was broken and that my girls and I are lucky that we were not seriously injured. The car was towed to the Mazda dealer service department 4 days ago and I have not heard from them. Is this something that is covered under tread liability laws? …
While making a right turn into a parking place, the right front ball joint broke and cv joint became disconnected, causing the wheel to become disconnected from the car and pushing the wheel well back under the passenger door, making it inoperable. The tow driver said I must have hit something really hard, but in the two and a half years I've had this car, I've never hit anything! I drive a lot for my job and am grateful this didn't happen while I was traveling 70 MPH on the highway. It was very scary and has shaken my confidence in this car. I had the car repaired on an emergency basis, but the mechanic told me while the other ball joint was safe enough for me to make the trip home (350 miles), I should definitely get it checked out as well, as it looked suspect for the long term. The car is at the mechanic now, and I was a nervous wreck driving it home earlier today.
Car make weird vibration noise in the back end . Went to different mechanics and it's a transfer case and driveshaft issue. . Looks the problem is in design. Mazda recalled the transfer case from 2010 model and later but not before. Since the same part is used in earlier models requesting recall on earlier models too. I went to 4 different transmission shops and everyone told me that each and every Mazda CX-9 comes to them has same issue. Called dealership and they said the extended warranty is after 2010. They have same parts and I or other owners can't afford the repair and it's a manufacturing fault. Looking forward to get help from NHTSA
When accelerating after driving for a few minutes maybe 10-15 after the vehicle has had time to warm up, as I am applying pressure to the gas pedal and it is shifting into gears (usually into gears 3,4, & 5) the vehicle is showing that it is into the next gear but you feel it shift after the fact so it is delayed and as accelerating it feels as though it is lagging and trying to shift but can't fully right away. I am only submitting this complaint because I know a couple others with this make of vehicle but different years and they stated they have the same issue with their vehicle as well
My wife was driving the kids and all of the sudden the car started to make loud noise could not move forward and forced her to stop. Next day we towed to the mechanic's and was told the differential was cracked and it has been several cases of this happening to this car. A week after getting that fixed, I still hear notices when I am driving below 30mils. Now the mechanics tells me the back axle is leaking oil right next to the back differential. This needs to be investigated before a lose of life. If my wife was driving in a highway, there would have been a major accident.
Gear oil leaking out of the transfer case vent tube. This is not a normal function. Only way to check level is to remove fill plug and stick finger in. The only safe way to get to this is putting vehicle up on a lift. Researched online and many others are having similar issues. If not caught right away transfer case can fail along with transmission. There is no info on changing this oil at certain intervals. Failure of these two components can happen while driving and could result in injury. I think this should be looked into.
Transmission complaints in other CX-9 years
Frequently asked questions
How common are transmission problems on the 2008 Mazda CX-9?
NHTSA has 27 complaints about the transmission & drivetrain of the 2008 Mazda CX-9, 16% of the model year's 172 complaints. The component named most often is automatic transmission (2 mentions).
Is there a recall for 2008 Mazda CX-9 transmission problems?
No. NHTSA lists no transmission & drivetrain recall for the 2008 Mazda CX-9, though it has 5 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 2008 Mazda CX-9 transmission problems start?
Half of the complaints with a recorded mileage happened before about 104,000 miles, and 20% before 25,000 miles.
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.