2006 Ford E450 Transmission issue

[Rolin]

Traveling over the Rocky Mts in 100 degree heat the transmission fan ran occasionally. After a stop for lunch the transmission ran when we started up and went into limp mode when we tried to accelerate onto the freeway. It recovered but acted strange for a bit. The next day we had it serviced, flushed, new fluids. Seemed to work ok. On the way home we noticed after a long pull it made a Shhhhhh sound that would get louder, but stop when you let off of the gas. If we stopped for a short time everything worked ok. Noticed that the transmission fan never came on anymore.

Anyone had this sort of problem? I think maybe the temperature sensor is bad.
Rolin

[Rolin]

Ok, My ongoing problem may not be the transmission. I am learning more as I search the internet.
1. The temp sensor inside the transmission is to control cold (0 degrees C or below) shifting patterns. So that is probably not a problem.
2. Engine coolant temp sensor is what is used to change voltage to the PCM (power train control module)
3. The Tow/Haul light will blink on/off to indicate a transmission fault. I did not noticed it blinking during our trip. However, I didn't know to look at it.
4. The transmission works correctly, the engine runs ok.

Just have this weird sound that occurs after pulling a long hill when the transmission has shifted down. Then we start getting a Shhhhh noise that increases with throttle pressure and stops when coasting. After stopping, the noise goes away.

So at this time I am flummoxed. No clue to what is causing my issue and not enough info to help diagnose a problem.

Thanks for your inputs.
Rolin

[Rolin]

I don't have a temp gauge and my older Scan Gauge does not have transmission temperature as a display option. I am working to see if I can upgrade.

The only indication that the transmission was hot was that the cooling fan was cycling on and when leaving after lunch it didn't seem to shift correctly.

When pulling onto the freeway there was no power, it was like in a lower gear and would not accelerate. Like the engine and transmission said...we are going on strike. Had this happen to another Motor home pulling out of Death Valley on the West side, hilly, curvy and hot. Engine was not over heated. But transmission was not happy. That is my only reference point.

I don't understand exactly what Tow/haul does. I try to use it most of the time, but was experimenting to see what seemed to keep the transmission happy so we could limp home.

[rjstractor]

Rolin wrote:
Thanks for the responses.
I believe that the 2006 E450 transmission has a temperature sensor. It is inside and you have to drop the pan and remove the filter to access it. Also the sensor will activate an electric fan in front of the radiator if the transmission oil gets too hot because there are oil cooling coils in front of or built into the radiator. If you can confirm or correct my information please do.

I have a scan gauge and have checked for any codes and there are none. This is probably not as complete a test as a Ford garage can run.

I never had a Check Engine light come on during the course of our trip.

To minimize the problem during the last half of our trip we did not run the airconditioner or defroster. We did not use Tow/Haul and tried to keep the transmission locked in overdrive as much as possible...just let it slow down on the hills but would shift down if we got below 45mph.

I am trying to gather as much information as possible before I schedule an appointment with the local garage (would like to save time and money if possible).
Thanks,
Rolin

Do you have any actual evidence of the transmission overheating other than the report of it going into limp mode? Did the display specifically say that the trans was in limp mode? What did the trans temp gauge read? I didn't realize that trans had its own cooling fan. I agree with Grit, tow/haul mode should help the trans run cooler under load- a motorhome is always "hauling". It helps the engine run cooler as well.

[Grit_dog]

Rolin wrote:
We did not use Tow/Haul and tried to keep the transmission locked in overdrive as much as possible...just let it slow down on the hills but would shift down if we got below 45mph.

These are literally the 2 worst things you can do to the transmission from the drivers seat, short of maybe shifting it into reverse at 55mph..., if trying to lessen the stress on the trans or run cooler. :S

[Rolin]

Thanks for the responses.
I believe that the 2006 E450 transmission has a temperature sensor. It is inside and you have to drop the pan and remove the filter to access it. Also the sensor will activate an electric fan in front of the radiator if the transmission oil gets too hot because there are oil cooling coils in front of or built into the radiator. If you can confirm or correct my information please do.

I have a scan gauge and have checked for any codes and there are none. This is probably not as complete a test as a Ford garage can run.

I never had a Check Engine light come on during the course of our trip.

To minimize the problem during the last half of our trip we did not run the airconditioner or defroster. We did not use Tow/Haul and tried to keep the transmission locked in overdrive as much as possible...just let it slow down on the hills but would shift down if we got below 45mph.

I am trying to gather as much information as possible before I schedule an appointment with the local garage (would like to save time and money if possible).
Thanks,
Rolin

[klutchdust]

FWIW. My friend Jerry ran a transmission repair shop for 30 plus years. It was not uncommon that a customer came in and mentioned that after having their transmission "flushed" it began to have issues.
Drop the fluid and replace the filter is enough when servicing your transmission he advised.
Now, your issue was before you had it flushed but something to think about as we motor on down the roads......
Also, when climbing hills, turn off the AC. Heat generated by the AC contributes to increases in water and oil temperatures. Up front you have various coils for AC, transmission and then the big one, your water radiator. All competing to dissipate heat away from important stuff.
Best of luck getting your Rig back in service.

I carry a code scanner in my rig to help diagnose issues while on the road. Also many auto stores will scan free of charge. The scanner reads code ***. you look up code *** on internet and bam, you are more informed of your issue.

[bobndot]

Taken from mechanic on Ford truck forum:
Might be worth considering.

Ok here is what you need to do the wrench light is coming on due to either a trans malfunction or a throttle body malfuntion. You need to take to ford dealer and have the codes ran to determine what codes you have. If the throttle position sensor that is built in the throttle body is intermittenly acting up that will cause your problem. Also there is a oss sensor (output speed shaft) that is internal to trans where the valve body mounts that has given us some problems as well but after you have the codes read we will have a better understanding of what is going on and which system is causing your problem let me know what you have so we can get to the bottom of the problem.Hope this information helps thanks

[cbigham]

No idea what a transmission fan is. U mean engine fan?