07 F-150 trans fault

[mosseater]

Truck in sig picture, 5.4 liter, 4spd, 4:10 rear. I know I'm towing at max CGWR of 15,300 or better, but this "trans fault" has been coming on with more regularity in the last two years. This weekend while traversing 7 Mountains on Rt. 322 here in PA, it started kicking the engine fan on right at the bottom of the hill, and shortly thereafter, the "trans fault" came up on the screen.

I detect no discernable change in performance when this happens. Once, two years ago, I was able to pull over within a 1/4 mile and shoot the trans pan with my IR thermometer and it was well within temp limits at around 250. I'm going to get it checked, but I'm wondering if this might be a sensor somewhere screwing up the computer parameters and sending a false code. The fluid looks and smells brand new (changed and flushed by dealership less than 20K miles ago) and there is no slippage. Not sure what to think. The engine temp needle never goes above 1/2 way up, even in the extreme summer heat and towing. I suppose once a fault is triggered, it stays in the computer until cleared? Would that mean they'd be able to pinpoint the issue with the reader? Thanks for any input.

[gijoecam]

Indeed, and let's you monitor most engine parameters in real time. I use mine daily!

[mosseater]

gijoecam wrote:
Get yourself an ELM-27 OBD-2 bluetooth adapter off NewEgg or Amazon and spend the $6 for the Torque app for a smart-phone or tablet (assuming you have one, of course...) You can monitor the trans temps and check the code yourself when the light comes on and know with confidence what's triggering it. You can also monitor the torque converter slippage to help determine if that's happening/getting worse with time. (My guess is that it is) I've been watching mine for this issue for a while now (and I'm happy to report I've not experienced it thus far)

That looks very interesting! So, I plug it into the truck and it reads computer parameters via bluetooth to my Android phone? Do I have that correct? Sounds pretty sweet!

[Fast_Mopar]

Mosseater, I posted earlier on this thread about the trans codes not being stored. That is what the Ford dealer told me. However, last Friday my Ford left me on the side of the road, and I had it towed to a really good small private transmission shop in the area. They were able to read the codes. I guess my Ford dealer was not on the ball. Sorry about the incorrect information.

[gijoecam]

Get yourself an ELM-27 OBD-2 bluetooth adapter off NewEgg or Amazon and spend the $6 for the Torque app for a smart-phone or tablet (assuming you have one, of course...) You can monitor the trans temps and check the code yourself when the light comes on and know with confidence what's triggering it. You can also monitor the torque converter slippage to help determine if that's happening/getting worse with time. (My guess is that it is) I've been watching mine for this issue for a while now (and I'm happy to report I've not experienced it thus far)

[Grit_dog]

If it only does it when towing hot n heavy then it IS a heat issue, not a random short. Sounds like the TC is not locking up when it should or completely.
Have you marked the rpms at particular speeds driving empty to compare to rpms when you're pulling hot uphill?

[mosseater]

Bump to the top for those who wanted to know.

Took it to the trans shop today and they checked it out. Talked to the owner, who was at least 70, been in trans business probably since auto trans was "new". He was explaining things in detail way over my head, but the summation was that unless we can get it to go into fault and stay there, and unless we can drop the pan with certainty as to what we're looking for, I need to keep driving it until either something definitive happens, or my wallet gets to fat. At this point, there's nothing wrong that they can see and it's probably pointless to tear it apart until there is.

He did bring up the same code my other mechanic found and said he's seen solenoid wires crack or break which might cause the intermittant issue I'm seeing. I was curious to know why, if that was the case, doesn't it do it at other times during normal driving? Only when I'm pulling the trailer up a hill and running it hard. He said hard to know. Could be the solenoid isn't flowing enough of a leak during normal driving to show a code. He claims it won't hurt anything by driving it the way it is even if the code comes on.

For now, if the code comes up and stays up, then bring it in. Otherwise, don't worry about it. AND, the visit today was FOC! Even though I'd like to find the problem and get it fixed, this at least gave me a level of peace of mind. Maybe it'll never come up again. Maybe it'll puke parts all over the pavement next week. I'm done worrying about it in any case, for now.

[mosseater]

Quick up date. I took the truck to my buddy's garage and he was able to bring up a code #P1744 "torque converter clutch system performance". When I Googled that code it shows that the converter clutch solenoid valve may be hanging up not allowing the converter to lock in fully, which created more heat. Im not going to type in the entire text, but if you folks want to know, just Google the code. It wasn't hard to find.

Tomorrow I'm taking it to a local reputable trans shop and he's going to take a look. Hopefully this problem won't be too devastating to the pocketbook. I towed locally this weekend and the alarm didn't come up so I have a feeling it's intermittant. When I spoke to the guy at the trans shop he seemed to feel the flush fluid changes can be detrimental because it can distribute magnetic wear particles through the trans to places they wouldn't normally be,(like clutch solenoid valves?) so maybe I've been doing myself an injustice by trying to keep up with more regular fluid changes.

I'll post tomorrow's results later.

[mosseater]

Mark Kovalsky wrote:

mosseater wrote:
OH, great! Not too convenient to reroute my camping trip to the nearest Ford dealer and let it idle while they find time to help.

Why would you have to leave it idle? When the light is on a code is stored in the computer. It will stay in memory for about a month after the last time it flashed. If they tell you they can't read it when the light isn't on, they are right, they can't. A competent tech can, but they can't.

mosseater wrote:
On a brighter note, I found several references to the same fault display and one guy who had his fixed. Turned out to be a temp sensor in the pan. Unfortunately, they dropped my pan and changed the filter when they did the last trans service. Hate to go back in just for a sensor. If I can find out which one and where, I might give it a go myself. After that spark plug fiasco, this should be a breeze.

You're going to start changing parts based on what was wrong with somebody else's vehicle? Good luck. There are at least 50 different reasons that the light could be on. You could spend thousands in replacing good parts before you get lucky and change the right one. Get the codes read and then I can help you find out EXACTLY what's wrong.

Actually, no, though I can see why you thought that by my wording. I've been in maintenance and repair for most of my career, so conspiciously absent in my response was the inference that I would need to know with at least probable certainty, which sensor and where before I go about changing it. That was the "if I can find out which one and where" portion of the sentence. I'm not a parts replacer. Never have been. Now, OTOH, if the probable cause points to a particular part with relative certainty, and the cost of absoulute confirmation will outweigh the cost of the part, then yes, maybe I'll be a "parts changer" in that scenario. Depends on the part and difficulty of replacement. I have worked with parts changers. Am not one. That's not trouble shooting and many times does not define the root cause of the problem. That is a road to expensive disappointment. Sorry for the confusion.

[Mark_Kovalsky]

mosseater wrote:
OH, great! Not too convenient to reroute my camping trip to the nearest Ford dealer and let it idle while they find time to help.

Why would you have to leave it idle? When the light is on a code is stored in the computer. It will stay in memory for about a month after the last time it flashed. If they tell you they can't read it when the light isn't on, they are right, they can't. A competent tech can, but they can't.

mosseater wrote:
On a brighter note, I found several references to the same fault display and one guy who had his fixed. Turned out to be a temp sensor in the pan. Unfortunately, they dropped my pan and changed the filter when they did the last trans service. Hate to go back in just for a sensor. If I can find out which one and where, I might give it a go myself. After that spark plug fiasco, this should be a breeze.

You're going to start changing parts based on what was wrong with somebody else's vehicle? Good luck. There are at least 50 different reasons that the light could be on. You could spend thousands in replacing good parts before you get lucky and change the right one. Get the codes read and then I can help you find out EXACTLY what's wrong.

[BenK]

First, congrats on the 8.2K half ton...a very rare truck

7 lugs to differentiate from a 'normal half ton' (6 lugs) and a 3/4 ton (8 lugs)

You do need to find the root cause and fix that

250*F at the side of the pan says inside the tranny has the ATF much higher and
most likely why it set the code.

Again, suggest you find the root cause.

Maybe partial blockage of the run to the main radiator, or to the external ATF
cooler (they should be series)

Gotta find these things based on this indicator of potential failure out in the
boonies...

[Hannibal]

If I remember correctly, the Dodge 47RE would light a bulb on the dash if the transmission temp reached 256*F (Blue shop manual). This would cause a shift to direct drive (3rd) and lock the torque converter to help cool things down. Once cooled it would allow a shift to O/D. Sounds like it may be the same scenario. Sticking anti-drainback valve in the cooler line?

[mosseater]

My configuration has the 8200 GVWR package, 2200 lb payload, don't know for sure, but I've heard upgraded radiator, does have a trans cooler, 7 lug wheels, not sure what else.

Won't dispute anyones take on my trans temp, might well be correct. Not 100% sure 250 was the actual reading, but sticks in my head. I know I've taken readings before with the same IR thermometer on summer days while NOT towing and have been in the 190 degree range. My measurement was taken directly on the side of the pan at midpoint and about 6" away so I could rule out spill-over of the IR sensor from other sources. Wouldn't guarantee it, but I believe the reading was pretty accurate (other than my memory of the exact temp number). The strange part about the fault coming on this trip, both times, was that it came on so early on the hill. Both times I had been towing for over an hour and had already scaled hills nearly as steep as the runup to the mountain where the warning came on. Ambient temps were mid 50's. In fact, on the way back home, the alarm actually came on when I had just ascended a moderate grade and had leveled off right before the steeper grade. IOW, I was actually going slightly downhill before starting up the steeper grade when the alarm came on. No other hills on the two hour trip made the alarm come on, though to be fair, unless I stop and shut it off to reset it, I'm not sure the alarm will sound again, so maybe a temp alarm was triggered, but because the initial alarm wasn't reset, I never heard it.

As I get further into this situation, I'll update my finding here. I'll start recording readings the next time I drive it to get a data base going. Thanks all for the input.

[lbrjet]

Get yourself a Scangauge and start monitoring your water and tranny temps. Ford gauges don't move a bit until you have SERIOUS problems. 250 is way too high.

[BenK]

Personally think 250*F is too high and note that, that is the temp where it is
measured. Typically at the test port, but not the hottest point and that is at
the tips of the TC vanes where the shearing occurs...your fluid was hotter

More so if that temp was measured at the sump/pan...it is WAY hotter inside
the tranny

Personal, as many advisors here say: "it is good for it", "designed for it", etc

I'm not one of them and think keeping ATF as cool as possible while high enough
to vaporize condensation. This also provides lots of head room for those difficult
climbs

High temps will NOT cause instant failure, but will sooner than later

Sustained high temps has a greater potential of creating nasties in the ATF and
will coat (mainly varnish) precision mating parts...breaking down the AFT, etc

Why the OEM's invented the TC lockup. To remove shearing of ATF when
no torque multiplication needed, or slippage for gear change

I'd love to hear how this works out and hope it is just as others said...a
faulty something or other