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5r110w Ruh Roh

While driving home from work in what had been my flawless, 63,000 mile, '05, 6.0 powered Superduty, a chime went off, the towhaul light started flashing, and the message center was telling me to check transmission temp. When I looked at the transmission temperature gauge, it was on the peg COLD!

After I got home, in a panic I called the dealership. I was told they couldn't get me in for several days and it would cost 150.00 diagnostics at which point they would go no further until I was talked to.

Welp, over the weekend I did a search (thanks Al Gore) and found the following (and many similar) post on a message board;

My 05 trans gauge will be working then just lay over on cold then my message board will come on to check trans temp and my tow/haul light blinks.

This was followed by this:

It sounds like you have a bad temperature sensor.

Once you remove the pan locate the sensor in the valve body and remove the electrical connector very carefully. The sensor is about the size of a pen cap. To remove the sensor carefully unlock the stop tab and twist it, pull down to remove it. It comes out before a full quarter turn is made. Put it back in the reverse order. When you get the sensor to come out be prepared to catch the trans fluid that follows behind it, you will get less than a quart out of it.

Background info:

The transmission fluid temperature (TFT) sensor twist-locks into the solenoid body. The TFT is a temperature-sensitive device called a thermistor. As the transmission fluid temperature rises, the TFT resistance decreases. The powertrain control module (PCM) monitors the voltage across the TFT sensor to determine transmission fluid temperature. The PCM uses the TFT signal as an input to determine cold and hot temperature shift and TCC scheduling.

BTW - the temp gauge is a glorified "idiot" light as its response is severly dampened. Between 100-220F the needle will remain in the same position on the gauge. At 230F it will move up slightly to the middle of the normal range. At 250F it will move to Yellow, seal damage occurs at 250F after moderate exposure time. At 280F the gauge will move to Red.

I contacted Vince and he was kind enough to supply me with the appropriate pictures and yesterday I ordered the sensor, a case of Mercon SP, and a filter. Last night I drained and pulled the pan changed out the sensor and put her all back together. After driving it to and from work today, everything worked perfect and I've declared it fixed.
 
Last edited:

lil_dq

Let 'er eat boys!
6,933
265
Union, MO
Glad to hear it. How many naps did you have to take to get the job done?? LOL
 

d-kuzmen

Master Ford Tech
2,109
79
Connecticut
Congrats on your repair! Watch out, Vince will have you down at the shop helping him pull some 6.0's apart!
 

Skandocious

Post Whores Make Me Sick
19,076
655
California
To quote my PM to him:

Skandocious said:
Oh cry me a friggin river. I'm less than HALF your age and I'd be rich if I had a nickel for every time I washed a petrol product out of my hair :headbang:

Ya big baby :p
 

radialarm

Clown of Death!
It's a damn shame you got it fixed, I was going to offer you $250 bucks as is!!!
 

radialarm

Clown of Death!

radialarm

Clown of Death!
I also showed goose how to install the official FTF tracking device.
It wont help as I'm sure he put a "FordTruckFanatics.com" sticker on it!!!
 

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