FORD DPS6 TRANSMISSION PROBLEMS

[windguy]

Just read an article on MSN linked below about the problems with this transmission. Sounds like a nightmare.

Anyone else been following this?

 

Glad the Gen 2 TC has a different transmission = 6F35.

Not sure what the Gen 1 model has.

 

https://www.msn.com/en-us/money/companies/ford-knew-focus-fiesta-had-flawed-transmission-sold-them-anyway/ar-AAEb0x6

 

 

 

 

[Fifty150]

The 6 speed transmission is weak.  But not defective in design.  

 

I see a lot of police cars in the dealership with transmissions out.  The 6 speed transmission does fail under severe duty and pursuit.  There's an upgraded cooler.  There are different calibrations for shift strategy.  But probably not much different internally.    A police car could log a lot of hard miles in a year. 

[zalienz]

6 hours ago, Fifty150 said:

The 6 speed transmission is weak.  But not defective in design. 

Dude, dream on. The DPS6 is definitely defective in design. Read the emails from Ford engineers stating that software calibrations could not be made to make the vehicle driveable. The DPS6 was used in Fiesta and Focus models with a dual dry clutch design. Police use Explorers and Edge primarily, they use a different trans, as does the Gen 2 TC. I'm not clear on the Gen 1 TC.

Edited July 15, 2019 by zalienz

[Double Nickels]

That dual clutch transmission was known to be bad, and Ford sold them anyway.  I don't understand that.  This could turn into a lemon law buyback, like Chevy had with that defective small car they sold.  

 

The Explorer, Escape, Transit Connect, Edge, Taurus.....have different versions of a transmission jointly developed by GM and Ford.  Mixed results.  No obvious consistent defect.  But a lot of wear and tear is causing failure with fleet use.  For light usage, with more service intervals, they are working okay.  Just don't drive it 24 hours aroun the clock or chase anyone with lights and sirens.  Change the lifetime fluid every 30,000 miles.  

[Fifty150]

On 7/14/2019 at 8:34 PM, zalienz said:

 The DPS6 is definitely defective in design.

 

Police use Explorers and Edge primarily, they use a different trans, as does the Gen 2 TC. I'm not clear on the Gen 1 TC.

 

 

Sorry.  I wasn't clear.  My fault.  I meant the 6F series.  6F35, 6F50, 6F55.  Like what's in the 2nd generation Transit Connect.  

 

As I recollect, a lot of complaints about the Ford 4R 4 speed transmissions also.  People called those weak.  Complaints regarding longevity and service life.  Same as you hear now about 6F transmissions.  Yet millions of these are in use across the world.  Many still running fine

 

I wonder what the transmission failure rate is, and what is acceptable. 1 transmission failure out of 1,000, 10, O00, 100,000?  Hondas have notoriously weak automatic transmissions.  But they keep selling weak trannies in larger cars with bigger engines.  And Ford will even sell a transmission known to be defective.  

 

But then again, some companies sell an entire car which they know is defective.

Edited July 17, 2019 by Fifty150

[Appraiser249]

My wife uses her 2015 TC to deliver mail, lots of start & stop driving.  The lack constant travel makes everything hotter than normal since there is little air flow.  Once she got transmission error message.  The dealer said she was a quart and a half low on trans fluid and that we may need to change the fluid more often than 150,000!   She's going to be off next week so the fluid will be replaced even though there is only 115k on it.  We got it with 95k.  

 

Does anyone make a transmission cooler to supplement the little one from the factory?  

[Fifty150]

An aftermarket cooler should be installed inline with the return line.  Never install an aftermarket cooler as a bypass or delete for the OEM cooling system.  The best location on your 2015 will probably be behind the grille/bumper cover.  You will need to fabricate mounting.  You will need to splice into the transmission return line.  You can do this yourself, with a few hand tools, basic mechanical skills, and probably a few hours. 

 

2 hours ago, Appraiser249 said:

Does anyone make a transmission cooler to supplement the little one from the factory?  

 

From what I've seen, not one transmission cooler is specific to the Transit Connect.  You may be able to source an auxiliary cooler made for use with a similar vehicle like Ford Kuga, Fusion, Focus, or Escape.  You may even find a cooler made for the Police Interceptor Explorer.

 

The lowest priced coolers, tube & fin, are the least efficient.  The advantage to the least efficient cooler is that with the tube sized the same size as your OEM transmission lines, it is least likely to clog and your fluid should flow freely.  Tube & fin coolers have been around a long time, and were once very popular.  Any extra cooling, even with tube & fin, is better than nothing.

 

The plate & fin and stacked plates are known to be the most efficient design.  Contaminants in the fluid can collect in the plates and obstruct the fluid flow.  Stacked plates and plate & fin have been known to clog, and flushing out the cooler is maintenance which is suppose to keep the cooler clean.  But once the cooler is clogged, you stand little chance of actually cleaning out the plates and restoring the cooler to new condition..  A lot of people simply replace the unit with a new one, as opposed to trying to clean it.  

 

I would look at a transmission cooler with an electric fan.  There are very expensive models, with the fan already mounted, and a thermostatic switch installed.  The real problem is that the expensive coolers have the ON/OFF set for about 180 degrees Fahrenheit.  If the fluid has already passed through your cooling system, and it's still 180 degrees when it gets to your transmission cooler......you can only guess at how hot it must be when it exits the transmission case to the cooling line.  With the 180 degree thermostatic switch, the cooler on my truck never turned on.  Fluid was just a lot lower than that temperature in the return line.  When I modified the cooler with a 140 degree thermostatic switch, I see the fan turn on occasionally.

 

You can buy a cooler, buy a fan, and buy the fan controller for less than half the cost of an assembled retail unit.  

 

DeRale, B&M Racing, & Flex-A-Lite are known brands which offer good products with warranties.  In today's market, there are a lot of similar items from sellers I've never heard of.  I've tried parts from better known brands & unknown brands with varying results.  

 

Start looking around at Jegs & Summit Racing just to get an idea of what this may cost you.

 

 

 

 

 

[Appraiser249]

Thanks, that's a lot of good information to digest!  She said today it was shifting funny, which is the first sign that its low on fluid.  I wish there was a simple dip stick to check and add fluid.  The summer heat and some of the wild routes she has had to run lately are pushing the tranny a little too much.  She loves the room and everything else about the TC as a mail vehicle.  Really need to get some RHD ones over here from Europe!  

[Fifty150]

1 hour ago, Appraiser249 said:

 I wish there was a simple dip stick to check and add fluid.  

 

 

Adding fluid is pretty easy.  Just add through the vent cap.  The check port on the side of the transmission is not hard to get to.  

 

But that's not what you want to do.  You don't want to just add a little fresh fluid to top it off.  You need to service the transmission.

 

It sounds like you should set a couple of hours aside, and service the van. With that many miles, and considering that mail delivery is "severe service", plan to do a lot more than just an oil change.

 

Do the triple drain & fill.  You need to get as much of that old fluid out as possible.  Factory fill in the sump is 4 liters.  After the final drain, fill with 4 liters.

 

Since the van is up on jack stands or a lift, change the oil, do the brakes, exchange the rest of the fluids, and change the spark plugs.  Belts & hoses if you can.  You get the idea.  You bought the van used.  It has over 100,000 miles.  And it's your wife driving it every day.  Make it safe for her.

[Don Ridley]

You probably don't need an additional transmission cooler. As Fifty points out, this vehicle needs service. The existing cooling system should be adequate. You can read the transmission temperature with an obII device to verify. This may save time time and money.

[Double Nickels]

Other cars with 6FXX transmissions have auxiliary coolers.  Can't be that hard to source or duplicate the plumbing.  Auxiliary cooling may be beneficial for a car which drives all day, at low speed, with constant stop and go between mail boxes.  

 

After you perform all the service work, datalog the transmission.  It should be interesting to see which gears it shifts to during the work day, and what the temps are.  You will get a better idea of how well the OEM system cools with just the oil to water heat exchanger.

[G B L]

The cooler flow is controlled by a thermostat, so adding an extra cooler will not lower the running  temp of the transmission.  The  best protection for this gear box is regular fluid flushes and checking the fluid level regularly.

[Fifty150]

There is a diagram of a 6F35 with OEM installed cooler.  Comparing that to the parts diagram for 6F35 without the cooler, the only difference is in the placement of the cooler bypass valve.  You should be able to install and route plumbing in a similar fashion.  

 

The thermostatic cooler bypass valve will prevent "over cooling".  Fluid will flow into the valve, and back to the transmission, bypassing the cooler unless the fluid is hot enough to close the valve.  I'm not entirely sure of what the preset temperature is.  Most bypass valves close at 180 degree Fahrenheit.  

 

It appears as if in the stock Transit Connect configuration, the cooling line flows to a bypass valve, where it returns to the transmission, unless it's hot enough to require cooling.

 

The transmission equipped with the auxiliary cooler has the cooling line flowing straight to the heat exchanger, then a bypass valve.  So if the transmission fluid exits the heat exchanger, and it's at an acceptable operating temperature, it will bypass the cooler and return to the transmission. 

 

[Fifty150]

 

[Fifty150]

From Google searching 6F35, this image came up.  It seems to show that the fluid flow comes from the front, top of the transmission, behind the torque converter.  Fluid then returns back to the transmission in the rear of the unit.  I hope this helps.

 

[mrtn]

At what temp are your 6F35s running? Mine is 208F at highway speeds.

[Beta Don]

On 8/9/2019 at 10:17 PM, Appraiser249 said:

Thanks, that's a lot of good information to digest!  She said today it was shifting funny, which is the first sign that its low on fluid.  I wish there was a simple dip stick to check and add fluid.  The summer heat and some of the wild routes she has had to run lately are pushing the tranny a little too much.

With 115K on the original fluid in severe stop and go service, it may be the first sign you're about to spring for a new trans!  I changed the fluid in mine at 25K.  It's not a simple procedure, as there's no way to drain the torque converter, where most of the fluid is trapped.  Draining the case and refilling it gets you only about half new and half old fluid  -  Draining and refilling it 3 or 4 times is necessary to get a 90% or better exchange.  Cross your fingers and hope for the best

 

Don

[Fifty150]

7 hours ago, mrtn said:

At what temp are your 6F35s running? Mine is 208F at highway speeds.

 

 

I see between 190 - 210.  All varies depending on ambient temperature, drive conditions, whether the cooling fan is on or off, airflow from freeway driving, how heavy your foot is on the accelerator, and how much weight you have in the van.  

 

The idea is to regulate the engine and transmission temperatures to stay above 150.  I've heard that 150 is the magic number for open loop / closed loop operation, and learning/relearning drive cycle.  I could be wrong, but I've also heard the number 100 Celsius or 212 Fahrenheit as acceptable operating temperatures.  I've also heard that with modern transmissions, anything below 225 is fine, and that the temperature that you don't want to exceed for any duration is 250.  

 

Most OEM thermostats are around 180 or 190.  Engine coolant flows completely through the cooling system.  The transmission has a cooler bypass valve, which closes about 180 or 190.  Transmission fluid now travels to the heat exchanger.  In theory, the cooled radiator fluid brings down the temperature of the transmission fluid via the oil-to-water heat exchanger.  In the Transit Connect, it's a little finned device bolted on top ot the transmission.  Air flow and the fan, plus the radiator fluid, work together to cool the transmission fluid.  In a lot of trucks, transmission fluid is passed through the cool side of the radiator, which is a similar cooling method.  In some trucks, the transmission fluid then routes through an oil-to-air auxiliary cooler.  

 

Learn to trust & believe the electric scan gauge reading for transmission fluid temperature.  It's the same number which the car's computer uses.  Any other temperatures you read, from any gauges you install yourself, will be less relevant.

 

Consider that the temperature sensor inside of the transmission is suppose to be a pan temperature.  Much hotter fluid is in the torque converter, pumped out through the cooling line, then returns to the transmission.  Cooling line temperature is much higher than pan temperature.  Return line temperature is lower.  Which makes the pan temperature somewhere in the middle of the the hottest & coolest.  In larger transmissions with more fluid capacity, I've heard that the temperatures can vary even more, depending on where you are taking readings.  You can drive yourself crazy with setting up gauges and temperature probes.  Get a "point & shoot" thermometer, and you will really go nuts.  Temperature of fluid inside of the transmission lines, and inside of the transmission case, is not the same as whatever the thermometer reads when you point & shoot the outside of the transmission case, pan, lines, cooler, & fins.  Imagine pointing that laser thermometer at a BBQ, then pointing it at the meat on the grill, and then taking a reading by pointing the laser dot at the pile of hot coals.  

 

 

[G B L]

When I  have checked mine it is generally at 170 to 180 unless you are pulling hills or have a trailer on then it has approached 190 to 200.

I bet your highway speed is higher than mine.  The heat comes from the converter being unlocked .

[Fifty150]

Also drive duration.  if you commute less than XXX miles or XXX minutes.  Versus someone who commutes an hour, 50 miles, or more.  

 

According to different service manuals I've read over the years, for different models of transmissions.....most said to drive at least 10 miles and get the transmission temperature to 180, which is suppose to be an optimal operating temperature for checking transmission fluid levels.  By 180, the cooler bypass valve should be closed, and transmission fluid is flowing through the cooling system.  The Transit Connect 6F35 probably falls within that rule of thumb.  At 180, the transmission is "warmed up".  

 

For my short 10 mile commute to work, 170 - 180 is the transmission temperature when I park and turn off the engine.  It's when I'm driving the van around all day, or traveling for longer distances on the freeway, that I see the transmission temperature rise.  In my area, there are very steep hills.  Hills, with stop & go traffic.  Temperatures spike .Most people in The USA don't sit in stop & go traffic on the freeway or climb steep grades.  Not to mention freeways with steep grades, which you have to climb at 65 - 70 MPH, as the transmission has to downshift.

[Double Nickels]

On 8/10/2019 at 5:45 PM, G B L said:

The cooler flow is controlled by a thermostat, so adding an extra cooler will not lower the running  temp of the transmission.  The  best protection for this gear box is regular fluid flushes and checking the fluid level regularly.

 

 

I agree with your recommendation for fluid exchanges.  

 

No way to lower transmission cooler fluid to below the bypass valve setting unless you delete the bypass valve.  But there's no reason to do that.  

 

The real concern, and the reason for additional cooling, is if you tow, climb hills, carry heavy loads, sit in traffic, drive for hours like on a road trip or it a work van which runs all day, and your transmission fluid temperature runs to 225 or 250.  

On 8/11/2019 at 9:33 AM, mrtn said:

At what temp are your 6F35s running? Mine is 208F at highway speeds.

208 is nothing to worry about.  Watch your gauges.  Does it drop? Is there cooling?  What's the highest you have seen?

 

[mrtn]

It drops significantly in town. That's about the highest I've seen when monitoring, either at 70 mph and/or towing a trailer.

[Fifty150]

5th gear is the 1:1 ratio where the torque converter is locked.  6th gear is the overdrive.  I suspect that if you are towing a trailer at 70 mph, you are not in overdrive, and there is probably a lot of downshifting to 4th gear.  And your engine must be revving a little higher, spinning the torque converter faster, and heating up the fluid a little more.  Your cooling system is working as designed.  I would have thought that towing at 70 mph, the transmission temperature would be even higher.

[G B L]

The converter locks in most of the higher gears.  Unless you lock the trans out of 6 speed if the terrain is flat enough the trans will go into 6 and lock the converter.

When the Trans is running with the converter locked is does not generate any more heat than a standard gearbox.

[Double Nickels]

Another thing to look at is the reading for coolant temperature.  Mine shows 210+ when stuck in traffic.  Stop & go traffic also raises temperatures in the transmission.