Ford Flex Transmission Problems & Cost | 6F50

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.

Need a replacement transmission? Get an estimate for replacement transmissions and local installation. Look up your transmission model by vehicle make and model.

What Transmission Do I Have?

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:

TransmissionStreet Smart Transmission
6F50 / 6F352480

What are the DTC codes related to Ford Flex transmission problems?

Trouble CodeDescription
P0703Torque Converter/Brake Switch B Circuit
P0705Transmission Range Sensor Circuit Malfunction (PRNDL Input)
P0707Transmission Range Sensor Circuit Low Input
P0708Transmission Range Sensor Circuit High Input
P0711Transmission Fluid Temperature Sensor Circuit Range/Performance
P0712Transmission Fluid Temperature Sensor Circuit Low Input
P0713Transmission Fluid Temperature Sensor Circuit High Input
P0714Transmission Fluid Temperature Sensor Circuit Intermittent P0715
P0715Input/Turbine Speed Sensor Circuit
P0717Input/Turbine Speed Sensor Circuit No Signal
P0718Input/Turbine Speed Sensor Circuit Intermittent
P0720Output Speed Sensor Circuit
P0721Output Speed Sensor Circuit Range/Performance
P0723Output Speed Sensor Circuit Intermittent
P0729Gear 6 Incorrect Ratio
P0733Gear 3 Incorrect Ratio
P0734Gear 4 Incorrect Ratio
P0735Gear 5 Incorrect Ratio
P0748Pressure Control Solenoid 'A' Electrical
P0750Shift Solenoid 'A'
P0751Shift Solenoid 'A' Performance or Stuck Off
P0752Shift Solenoid 'A' Stuck On
P0753Shift Solenoid 'A' Electrical
P0755Shift Solenoid 'B'
P0756Shift Solenoid 'B' Performance or Stuck Off
P0757Shift Solenoid 'B' Stuck On
P0758Shift Solenoid 'B' Electrical
P0760Shift Solenoid 'C'
P0761Shift Solenoid 'C' Performance or Stuck Off
P0762Shift Solenoid 'C' Stuck On
P0763Shift Solenoid 'C' Electrical
P0765Shift Solenoid 'D'
P0766Shift Solenoid 'D' Performance or Stuck Off
P0767Shift Solenoid 'D' Stuck On
P0768Shift Solenoid 'D' Electrical
P0770Shift Solenoid 'E'
P0771Shift Solenoid 'E' Performance or Stuck Off
P0772Shift Solenoid 'E' Stuck On
P0773Shift Solenoid 'E' Electrical
P0774Shift Solenoid 'E' Intermittent
P0777Pressure Control Solenoid 'B' Stuck On
P0778Pressure Control Solenoid 'B' Electrical
P0817Transmission Fluid Pressure Manual Valve Position Switch Reverse with Drive Ratio
P0817Starter Disable Circuit
P0960Pressure Control Solenoid “A” Control Circuit/Open
P0962Pressure Control Solenoid “A” Control Circuit Low
P0963Pressure Control Solenoid “A” Control Circuit High

Ford Flex Transmission Recalls

None Found

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
Leaking Fluid
Low Fluid
Burning Smell
Grinding or Shaking
Whining, Clunking or Humming
Refuses to Go Into Gear
Torque Converter Issues
Valve Body Issues
Transmission Noisy in Neutral
Gears Slipping
No 3rd or 4th Gear
No 1st or 2nd Gear
No Reverse
Dragging Clutch
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.

Need a replacement transmission? Get an estimate for replacement transmissions and local installation. Look up your transmission model by vehicle make and model.

What Transmission Do I Have?

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!

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6 months ago

It surges slightly when it gets in third gear. It’s kind of a jerking feeling. I had my BCM replaced about a month ago. I thought maybe it needs to be re-calibrated? 6F50 FWD
Ford flex 2016

Parker Lynch
10 months ago

My flex has been “grumbling” from 110,000 all the way to 120,000 miles and my mechanic says it’s a transmission issue, but claims replacing it would cost more than the car is worth. Other than the “grumbling” at low speeds, there ate the many more noticeable issues.

David Donner
11 months ago

It acts like it’s jumping in and out of gear when going up hill are just slowing down

1 year ago

2011 Flex Ecoboost AWD 147000. On acceleration the is a hard shift/shuttering between 3rd ad 4th.

Matthew Fuqua
2 years ago

I have a fwd 2009 limited, when speed reaches between 45 & 60 the car starts “jump/lurch” back and forth like it cannot decide what gear it needs to be in, I push the overdrive button on the side of the gear shift and then it’s back to normal and rides fine. The other issue I have is that my speedometer is not working properly, I’ll be sitting at a red light and my speedometer will read 80 mph or 120 or 90, etc. Etc.
The only way I can temporarily fix it is if I disconnect my battery for about 30 seconds and reconnect it. Sometimes I have to do that several times in a row until the needle drops to zero. This fix will last 1 to 4 days and then will act up again

Larry Johnson
2 years ago

2010 Ford flex tranny was slipping and grinding, would make motor rev while in gear. Bought used tranny with 60,000 miles had it installed,it is doing the same thing. Any ideas?

2 years ago

2009 flex front wheel drive, used transmisdion installed with 40k on trans, had ford reflash pcm for new trans, shift great from a stop but if you slow down for a redlight and it turns green say about 10 or 15 mph then get back on gas to go it will bang (very hard shift) (pretty sure its 2nd to 3rd shift,) up to three times really fast and hard, if you keep a light foot its not so hard or you can really give it the gas pedal till it shifts back to second and it will shift perfect all thru the gears.. help!

2 years ago

2009 flex front wheel drive, used transmisdion installed with 40k on trans, had ford reflash pcm for new trans, shift great from a stop but if you slow down for a redlight and it turns green say about 10 or 15 mph then get back on gas to go it will bang (very hard shift) (pretty sure its 2nd to 3rd shift,) up to three times really fast and hard, if you keep a light foot its not so hard or you can really give it the gas pedal till it shifts back to second and it will shift perfect all thru the gears.. help!

Casey schmitt
2 years ago

My sel flex has been shuttering while accelerating. But once it is up to about 50 it rides perfect. I was told I have an internal leak in the tranny? I also have gas mixing into the oil? Help! I just bought this car last month

tree greenleaf
2 years ago

my ford flex is super gay, its licks and sucks on my scotum while i drive while it gives my butthole i nice reach around massage

2 years ago

09 Ford Flex leaking fluid loud clunk pretty much every time I put it in reverse
Hard time shifting back and forth 60-70 mph

3 years ago

2010 Ford Flex Limited AWD has a cracking the transmission housing. Can the Housing just be replaced or have to replace the whole transmission?

J A Witkege
4 years ago

On my 2015 Ford Flex with only 59000 miles, I am getting a mild extra thud as I go forward through the first three gears. After that there is no noticeable extra sensation., The first thud is normally the most noticeable

4 years ago

2010 Flex AWD Turbo – symptoms: intermittent clunk into 3rd or 4th started happen more frequently, and now stuck in 3rd wont change up, manual mode wont engage at all ie the paddle shifters on the steering wheel don’t do anything. Mechanic says clutch is burnt out and have to replace or complete rebuild. $3-5000. though he hasn’t dismantled just driven and looked at fluid. He also says that rebuilders wont just fix whats damaged as they wont warranty unless they do all. I want to sell it so im ok with fixing only what is actually broken.

4 years ago

I had. 2 flex a 2010 & 2011 both. Had transmission problems. The 2010 started not going into drive gear & felt like you were in neutral then it would jerk & go into
Gear. The 2010 was not even out of warranty. I took it back several times. They could not fix it so I traded it in for a 2011. THE 2011 did the same thing but it was paid for & had about 120k miles. Estimate for new transmission was in the thousands. 5 Gave up
& bought a f150. I really want a 2019 flex but don’t know if I am ready for another nightmare with the transmission. Very
Comfortable car.

John “ johnny wadd” holmes
5 years ago

I damaged my speedometer cluster by accidentally jabbing it with a flat head screwdriver while trying to disconnect the harness. Knocked the gas gage out. Now I’ll get “service selecttrack” occasionally on the dash. I clear it on the “reset” button and it’s ok again. BUT yesterday as I was pulling into traffic while exiting from In & out, it suddenly the stopped responding! I had to limp 14 mph in horn honking traffic! I’m scared and totally confused! I go one block and pull into a parking lot. It starts to sound like a fan rubbing against a housing. I turn it off and start to look under the hood, nothing! Bought me and a crackhead water and got back in. Started up, put in drive and off to the races! Shifts fine, hit passing gear. Car only has 89.000 Texas miles. Went to O’railey and Jesus (why can’t he just heal it for a few love dollars) says he can’t hook up an ODB 2 UNLESS A LIGHT IS ON NOW! What could this be?

5 years ago

I have a 2010 Ford Flex FWD with 150k, when I excelerate from a stop or to a higher speed I have a shudder. Initially I believed that it was a bad CV which I replaced. It now seems likely it is the torque converter.

4 years ago
Reply to  Nick

Nick, did you ever get this fixed. We have been having this issue with our 2011 flex for a while now. Was told torque converter and would need to just replace the entire transmission. Not sure how much of that we should believe.

4 years ago
Reply to  Mal

Hey guys: My 2012 Ford Flex with just 120,000 miles may need new transmission. Dealer says it is the torque converter bur entire transmission must be replaced. Is this true?

3 years ago
Reply to  Laura

What did you do? I have a 2014 with 107,000 miles and was told the same.

1 year ago
Reply to  Tracy

I am going through similar (2014 w/ 115,000 miles). My local guy says the torque converters in the Flex are known to be of a poor design (and likely the clutch coming apart). You have to remove the transmission from the car to get to it. He is just recommending a repair/rebuild which could save up to $2000 over a complete replacement of the transmission.

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