Been a while since Ive been on here. I think I posted about this a while ago but can't find it.


07 F150 4x4 auto
139k

After long drives (anything over about 45 minutes) the clutch fan kicks on (loud) and the trans starts to downshift hard from 2-1. Also, while accelerating in 2nd gear the rpms fluctuate along with the sound of the clutch fan. It is not slipping, but rpms are going from high-low-high along with the clutch fan surging. while it's doing this if I accelerate harder, above 3500rpms it lets out a loud squeal (belt slip)

I've also had a few really hard OD downshifts while passing (very aggressive bang/shift)

Also, more recently while going up a steep gravel road incline the OD light flashes and trans fault displays. But as soon as I turn the truck off and on again, the light goes away. Which poses another problem.... I have talked to a ford tech about bringing it in to see what the code is but by the time I get down from where I am and back into town the code is no longer stored. This has only happened 3 times in the last few years and hard to get it to do it let alone get it into a tech before the code is cleared.

Someone mentioned a trans temp sensor. Otherwise I'm pretty stuck trying to figure this out myself unless I can get it in while the lights on which doesnt seem possible considering the steep roads I'm traveling are 2 hours from any dealer and I only go over them a few times a year.

NONE of these issues occur on shorter drives, shifts and drives like normal unless I've been on the road longer than a 45-1hour

20k miles ago got a full trans flush including tq converter (myself) with a new filter and OE fluids. Nothing out of the ordinary on the trans pan magnet.

Is it possible a bad clutch fan could be playing some kind of role? I need to pull that code. Would torque pro app for android work?

 

Are you sure the code clears? That isn't supposed to happen. The code is supposed to stay in memory for about a month after the last time the light flashed.

 

Called a Ford (dealer) tech right after I got back the other day and asked him if I could bring it in for diagnosis and he said if I had driven back 2 hours the night before, then to work the next day that the code was likely gone by the time I brought it in after work being it clears after a few drive cycles. Said to try and get it in with the light still on or had recently come on.

Not sure if that is the case. Maybe not. Maybe he just wasnt interested in looking into it unless it was more recent or still on.

 

I found and bought a really nice little code reader called a BlueDriver. Got it on Amazon for right at a hundred bucks shipped. It definitely reads manufacturer specific codes and will pull anything that is generated by a transmission issue.

BlueDriver

D

 

I'm sure it isn't the case. The code stays in memory for 30 engine warm up cycles after the last time the light flashed. Most people don't know that, including techs.

 

I wanted to post an update to this. Since the problem still exists even after a trans rebuild.


I never figured out what was causing those trans temps.
Fast forward to December of 17. Pulling a trailer for work on the highway and loose almost all momentum. Barely get it home slipping really bad. Next day, wont even reverse out of my driveway.
Call a trans shop down the road with good reviews and been in business for 20+ years and have them tow it.
They run diagnostics on it to make sure it's not electrical and that there was mechanical failure.
They tore it apart and verified it had burned up the clutches. I can't remember exactly what else but they went ahead and did a "full rebuild" with new torque converter. Full fluid flush through the cooler etc...at the cost of over 3,500

2 days after getting it back I'm on a long trip that I typically took before the trans went south low and behold... the clutch fan kicks on full blast around the same area it also does and the trans starts to shift a little odd.

Next day while driving in the city, trans fault light comes on and OD light flashing (same symptoms as before the rebuild) So I took it back to the shop. Shop guy seems nice enough to immediately acknowledge that this is an issue he will figure out and fix at his cost. So I drop it off for him to keep for a day to run some live data on and test drive it to try and get it to do what I was explaining.

Calls me the next day and says he thinks it's just fine and at worse possible that the temp sensor has gone bad sending a false signal and that it's not in any danger and I could come pick it up and schedule another time to drop it off for repairs. Busy holidays and such and have not had time to do that.

I have the feeling it is actually overheating and the problem was never fixed so I recently bought a bluetooth obd2 and running torque pro today. After driving in the city for just 25 minutes I watch the temps climb on the trans to 276 degrees. To verify it's not a false signal I have a fluke infra red thermometer and the trans pan and surrounding areas were reading 250 degrees so I'm assuming my trans is actually overheating for whatever reason.

Tomorrow I'm going on a really long trip and am going to see just how high it is going to go. Today I had to go home just minutes after it reached those temps but seemed as though it was going to continue to climb.

I plan to push this shop to fix the issues but any input is appreciated

 

Isn't there a thermostat in the cooler line that closes till the fluid reaches operating temp? It may be sticking shut.

 

Fluid cooler bypass valve?

Definitely going to have them look into this.