The Ford Flex was equipped with the 6F50 transmission. But they aren’t without their problems though, so let’s look at some of the most common Ford Flex transmission problems, look at cost estimates and figure out what you can do about them.
Ford Flex Transmission Models
Ford Flex: 6F50 Transmission
Ford Flex Transmission Replacement Cost Estimate
Pricing varies by model. To be 100% sure on pricing, have your VIN# handy and use our Get An Estimate feature to look up your transmission by VIN#.
Replacement 6F50 Transmission:
|Transmission||Street Smart Transmission||Autozone||Advance Auto Parts||Dealer Retail|
|6F50 / 6F35||2295||2355||2649||3387|
What are the DTC codes related to Ford Flex transmission problems?
|P0703||Torque Converter/Brake Switch B Circuit|
|P0705||Transmission Range Sensor Circuit Malfunction (PRNDL Input)|
|P0707||Transmission Range Sensor Circuit Low Input|
|P0708||Transmission Range Sensor Circuit High Input|
|P0711||Transmission Fluid Temperature Sensor Circuit Range/Performance|
|P0712||Transmission Fluid Temperature Sensor Circuit Low Input|
|P0713||Transmission Fluid Temperature Sensor Circuit High Input|
|P0714||Transmission Fluid Temperature Sensor Circuit Intermittent P0715|
|P0715||Input/Turbine Speed Sensor Circuit|
|P0717||Input/Turbine Speed Sensor Circuit No Signal|
|P0718||Input/Turbine Speed Sensor Circuit Intermittent|
|P0720||Output Speed Sensor Circuit|
|P0721||Output Speed Sensor Circuit Range/Performance|
|P0723||Output Speed Sensor Circuit Intermittent|
|P0729||Gear 6 Incorrect Ratio|
|P0733||Gear 3 Incorrect Ratio|
|P0734||Gear 4 Incorrect Ratio|
|P0735||Gear 5 Incorrect Ratio|
|P0748||Pressure Control Solenoid 'A' Electrical|
|P0750||Shift Solenoid 'A'|
|P0751||Shift Solenoid 'A' Performance or Stuck Off|
|P0752||Shift Solenoid 'A' Stuck On|
|P0753||Shift Solenoid 'A' Electrical|
|P0755||Shift Solenoid 'B'|
|P0756||Shift Solenoid 'B' Performance or Stuck Off|
|P0757||Shift Solenoid 'B' Stuck On|
|P0758||Shift Solenoid 'B' Electrical|
|P0760||Shift Solenoid 'C'|
|P0761||Shift Solenoid 'C' Performance or Stuck Off|
|P0762||Shift Solenoid 'C' Stuck On|
|P0763||Shift Solenoid 'C' Electrical|
|P0765||Shift Solenoid 'D'|
|P0766||Shift Solenoid 'D' Performance or Stuck Off|
|P0767||Shift Solenoid 'D' Stuck On|
|P0768||Shift Solenoid 'D' Electrical|
|P0770||Shift Solenoid 'E'|
|P0771||Shift Solenoid 'E' Performance or Stuck Off|
|P0772||Shift Solenoid 'E' Stuck On|
|P0773||Shift Solenoid 'E' Electrical|
|P0774||Shift Solenoid 'E' Intermittent|
|P0777||Pressure Control Solenoid 'B' Stuck On|
|P0778||Pressure Control Solenoid 'B' Electrical|
|P0817||Transmission Fluid Pressure Manual Valve Position Switch Reverse with Drive Ratio|
|P0817||Starter Disable Circuit|
|P0960||Pressure Control Solenoid A Control Circuit/Open|
|P0962||Pressure Control Solenoid A Control Circuit Low|
|P0963||Pressure Control Solenoid A Control Circuit High|
Ford Flex Transmission Recalls
Ford Flex Technical Service Bulletins (TSB)
TSB 10-22-4 – AWD vehicles – Shudder/chatter/vibration on turns or thump/clunk noise on light acceleration – 6F Transmission
2010 Ford Fusion – 2010 Ford Taurus – 2010 Ford Edge – 2010 Ford Flex – 2010 Mercury Milan – 2010 Lincoln MKS – 2010 Lincoln MKZ – 2010 Lincoln MKT – 2010 Lincoln MKX
Problem – Certain vehicles built between 10/1/2009-12/31/2009 equipped with all-wheel-drive, may experience a shutter or vibration in the driveline during a tight turn. They may also experience a thump or clunk noise during light acceleration. These symptoms may also occur under 40 mph (64 KM/H), when driving uphill or towing under heavy acceleration.
Solution – Installing a properly remanufactured PTU (Power Transfer Unit— a simplified transfer case) may solve this problem.
TSB 11-12-10 – Sluggish acceleration from 0-5 mph (0-8 km/h) followed by harsh bump or slip on takeoff – 6F35 Transmission & 6F50 Transmission
2010 – 2011 Ford Taurus – 2009 – 2011 Ford Edge – 2009 – 2011 Ford Flex – 2011 Ford Explorer – 2010 – 2011 Lincoln MKS – 2009 – 2011 Lincoln MKX – 2010 – 2011 Lincoln MKT
Problem – Some vehicles may experience sluggish acceleration or a hesitation feel during a rolling stop, followed by a harsh bump or slip feeling. This can be caused by a design flaw in the 6F35 valve body / 6F50 valve body.
Solution – On transmissions originally built for Mercon LV transmission fluid (listed on the dipstick), the valve body will have to be modified by deleting one hole in the valve body separator plate, and removing the check ball in the area of the deleted hole. If this modification is not performed properly, the transmission may experience a loss of reverse or a 2-3 shift flare.
TSB 15-0047 / 17-2219 – Push button start – Shift to Park or Transmission Not In Park message – discharged battery – unable to remove key
2011 – 2017 Ford Edge – 2011 – 2017 Ford Explorer – 2011 – 2017 Ford Flex – 2011 – 2017 Ford Police Interceptor Sedan – 2011 – 2017 Ford Taurus – 2011 – 2016 Lincoln MKS – 2011 – 2017 Lincoln MKT – 2011 – 2015 Lincoln MKX
Problem – Vehicles equipped with a floor shift selector lever and push button start, may display a ‘Shift To Park’ or ‘Transmission Not In Park’ message, even though the transmission is actually in Park. It may also not be possible to remove the transmitter key, and the battery may discharge due to the warning message remaining illuminated.
Solution – Install new park detect switch
TSB 10-21-2 / 10-17-4 – Slipping, 5th gear starts from stop, PRNDL display error, backup camera on while vehicle is in Drive – 6F50 Transmission & 6F55 Transmission
2009 – 2011 Ford Taurus – 2009 – 2011 Ford Edge – 2009 – 2011 Ford Flex – 2009 – 2011 Lincoln MKS – 2009 – 2011 Lincoln MKT – 2009 – 2011 Lincoln MKX
Problem – Certain vehicles may intermittently experience slipping, 5th gear starts from a stop, the electronic PRNDL display may flash errors, and the backup camera may be on while the vehicle is in Drive.
Solution – Install new Ford transmission range sensor / TR sensor.
Common Problems with the Ford Flex Transmission
Lack of Response
Grinding or Shaking
Whining, Clunking or Humming
Refuses to Go Into Gear
Torque Converter Issues
Valve Body Issues
Transmission Noisy in Neutral
No 3rd or 4th Gear
No 1st or 2nd Gear
Trouble Codes / Check Engine Light
Can I drive with a transmission problem?
If your Ford Flex can still make it up and down the road, you might say “It’s fine, I’ll just drive it until I can get it fixed”. But that is not always a good idea, depending on the symptoms. You see, there are a lot of (very expensive) moving parts inside of a transmission, and if something isn’t right, continuing to drive with a transmission problem could damage something else.
How often does a Ford Flex transmission need to be replaced?
The overall lifespan of a Ford Flex transmission largely depends on how well it was maintained. Factory design flaws also factor into this equation, along with how/how hard you drive. But on average, we’ve seen the Ford Flex transmission last for between 130,000-180,000 miles. A high quality replacement transmission however, can last considerably longer if all of the factory design flaws have been addressed and the vehicle has been maintained.
How are Ford Flex transmission issues diagnosed?
It is fairly easy to guesstimate what the root cause of your Ford Flex transmission problems might be, but you won’t truly know unless you have the right tools and experience. A good mechanic or transmission repair center will be able to connect your truck to a computer and find out which diagnostic trouble codes (DTC’s) have been stored. Once they know what to look for, they can perform a visual inspection to verify the problem.
How is a Ford Flex transmission replaced?
In order to replace your Ford Flex transmission, the truck has to be lifted from the ground in order to gain access to all of the parts that will need to be unbolted. Then the transmission can be lowered to the ground (typically with a transmission jack), so the new transmission can be installed. Once it is in place, for the 6L80, the vehicle PCM will have to be reprogrammed / reflashed to accept the new transmission using the latest GM subscription.
Recommendations for Ford Flex transmission issues?
To save time and get back on the road faster, have your 17-digit truck VIN# handy and you can get an online quote for a reman Ford Flex transmission here, then find a local shop using our Find a Shop guide to install it for you.
How to Solve Ford Flex Transmission Problems
Solution A: Buy a Used Ford Flex Transmission
The quickest way to fix your transmission problems is to simply buy a used transmission or used transmission. These can be found at most junk yards, and they often come with a 30-90 day warranty. However, there’s no way to determine the actual condition of the internal components, so you could be spending a bunch of money to have the exact same problems. Plus, that warranty only covers the transmission if it’s defective, not the labor costs that you’ll have to pay.
Solution B: Buy a Rebuilt Ford Flex Transmission
Another option would be a rebuilt transmission or rebuilt transmission. A local repair shop will remove your transmission, then install a bunch of new parts during the rebuild. The problem here is, the skills and experience of each transmission rebuilder will vary widely from shop to shop, so you could have problems from something that wasn’t adjusted properly. And the 1-2 year warranty might only cover you at certain transmission repair shops, in a specific geographical area.
Solution C: Buy a Remanufactured Ford Flex Transmission
Many owners depend on their vehicle to commute and get things done. Their gasoline engines are designed to go 100’s of thousands of miles, so it makes sense to invest in a remanufactured transmission.
What Problem Does Your Ford Flex Have?
Let us know the year, mileage and problem you’re having as well as any trouble (OBD) codes you’ve found. If you’ve been given a quote or paid for a repair, we’d like to hear about that too!