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 2009 Ford Flex owners, lightly cleaned up (personal details are redacted by NHTSA).
My Flex has repeatedly lost power while driving. I can feel the car lose power, and the yellow wrench light comes on. After reading up on it, I learned that you have to turn the vehicle off, wherever you are, and restart it after a few minutes. The wrench light turns off, and the car runs as normal, with no records of codes. This is talked about over and over in online forums. The safety issue is that it has happened on the freeway several times while traveling at a high rate of speed. The car loses power, and you cannot accelerate. You have to find a way to stop immediately, put the car in park (and listen to the transmission clunk) and turn it off. This last instance put me in harms way on the freeway. The car lost power while traveling 70mph. I immediately lost speed and had to cross 3 lanes of traffic to pull over to turn the car off. …
Transmission. When the temperature is 40 degrees or below I sometimes have an automatic transmission problem. In the morning after the vehicle was parked over night I start the vehicle, put it into reverse, I back 40 feet down my driveway which has about a 30 degree grade down to the street.. I stop on the street, put it into drive and turn to the right to proceed forward up the street with about 10 degree grade for about 300 feet, then the street has about a 15 degree grade for the next 200 feet after which it has a 5 degree grade for 75 feet at which point there is a stop sign at a busy two lane cross street that is fairly level and has a 35 MPH speed limit. I stop until the traffic gives me a 100 to 150 feet more break between passing vehicles so I can turn right, many times the engine revs to 4000 rpms but the vehicle accelerates vary slowly at picking up speed. …
Driving car, stopped at traffic light, or leaving places the transmission will not engage when put into drive. It gets stuck and won't move. This is very dangerous as I have almost been hit from behind when this happens. I have to put in park and try again and it sometimes shifts or makes a loud cluck and jerk. Happens off and on. Took into the Ford dealer couple of times and they said they could only determine what the problem is if it does it with them. Never does it when in the shop. The dealer acts as if they have no idea however I have read from several people that they have had the same problem with 2009 Ford Flex. I believe the transmission is the same as on the 2015 Ford transit vans because the same issue is happening with it. I have talked to my mechanic and they have heard of this problem too and told me to take the Flex into the dealer. …
My Flex started having a hard jerk and bang when going from reverse to park. Was not always but frequent. The car started to run hot when sitting in a drive thru or traffic but would go right back down when I started moving. I took it into s mechanic and he replaced the fan. After replacing the fan the car began to have a really bad grinding noise when idling or traveling. Do bad I did not want to drive it. I took it into the Ford dealership and after 2 days they call and say they can't find anything wrong. Within 4 minutes I get another call daying I need a new transmission. The car would eccellerate on its own, shut off intermittently, and car would lag between 3rd and 4th gears. Ford dealership advised me to have a knew transmission put in. Car will shift properly most of the time even on highway. Only get whining noise at low speeds. …
Tl* the contact owns a 2009 Ford Flex. While driving 35 MPH, the front of the vehicle began to vibrate. The vehicle was taken to an independent mechanic who diagnosed that the front axle had an indentation and the rear brake caliper had bolts that detached. As a result, the axle and caliper needed to be replaced. In addition, the technician stated that the torque converter and transmission seal were leaking oil and the drive line and torque converter needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failures. The failure mileage was 101,946. The VIN was unavailable.
Tl* the contact owns a 2009 Ford Flex. While the key was in the ignition, the anti-lock warning indicator illuminated. The contact was unable to start the vehicle. The vehicle was towed to an independent mechanic to be diagnosed, but the cause of the failure was not determined. The dealer stated that the secure lock system needed to be reprogrammed by the dealer. The dealer was not contacted. The vehicle was not repaired and the failure recurred. The manufacturer was made aware of the failure and transferred the contact to NHTSA to file a complaint. The failure mileage was approximately 169,000.
Car started 2 years ago with "stuttering" when driving between 50-60 MPH, as if the car couldn't determine which gear to stay in. Had transmission flushed and refilled in April 2016. Problem was less but still remained. Added dr shutter in June 2016 to the transmission fluid and problem has went away, that was last year. Paint on the hood is peeling and started out as a small chip May 2016, and is now the size of a 2 basketballs. Black body pieces that are between the windows on the side and in front by the windshield are loose and coming off. Will provide photos if needed
This in reference to the transmission, I have had it looked at and no one can seem to narrow down the exact problem. The vehicle stalls while driving. After stopping and restarting the vehicle it hesitates and the kicks into gear and drives. This doesn't happen every day, but not knowing when the vehicle might stall is troublesome. There is TSB 11-12-10 that describes this problem, the Ford dealerships do not have any safety recalls in reference to this.
Part of my power in my car shut off on the freeway, at 1:39 pm at 67 degrees outside . I had been driving for 40 minutes. My dashboard went dark, and only my clock time was on. I glided to the side of the road, and was able to pull the car very hard to the right (as the power steering was off). Then turned the key to off, waited 3 minutes turned the key and it went back on. It has not happened again.
Tl contact owns a 2009 Ford Flex. The contact stated that there was an oil leak on the rear of the engine. The engine was removed and the leak was repaired by the dealership. The air cylinder that lifted the third row seats was defective and had to be replaced. The rear hatch opened on its own five times; the dealer realigned the door to remedy the problem. The rear main oil seal failed so it was also replaced at the dealership. The brakes failed to stop the vehicle effectively. When the vehicle was taken to the dealership, they stated that the vehicle was fine. The battery was defective and was replaced. The transmission excessively shifted into gear when down shifting, causing the vehicle to jerk and shake. The dealer stated that they could not find a problem when they inspected the vehicle. The engine made a popping noise when he accelerated from a stop. …
Transmission complaints in other Flex years
Frequently asked questions
How common are transmission problems on the 2009 Ford Flex?
NHTSA has 23 complaints about the transmission & drivetrain of the 2009 Ford Flex, 13% of the model year's 181 complaints. The component named most often is automatic transmission (4 mentions).
Is there a recall for 2009 Ford Flex transmission problems?
No. NHTSA lists no transmission & drivetrain recall for the 2009 Ford Flex, though it has 1 recall 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 2009 Ford Flex transmission problems start?
Half of the complaints with a recorded mileage happened before about 76,000 miles, and 16% before 25,000 miles.
Is it dangerous?
Owners linked 1 crash, 0 fires 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.