Anyone have this problem with their Powerstroke?

2012 Ford Powerstroke with 6-speed Automatic transmission. 4 yrs, & 4 months old, 55,600 miles. I absolutely love this truck. This past Monday, we were headed North on the Rockefeller Parkway which connects Grand Teton National Park with Yellowstone NP, with Travel Trailer in tow. For those of you familiar with this area, there is a pretty good downhill grade as you approach the South entrance of Yellowstone. Speed limit was 45 mph so I had my Cruise Control set on 45 mph. On the downhill stretch, the transmission did it's job by downshifting in order to maintain the set speed. It shifted down to 3rd then 2nd. I IMMEDIATELY knew this was not right and so I switched off the Cruise Control as I saw RPMs reach into the 4000-6000 Redline area (maxed out at 4250 RPM). At most, it was here for 2-3 seconds. IMMEDIATELY, an audible alarm sounded, a Wrench icon appeared on Dash display as well as the Check Engine light. Also, Reduced Engine Power (or words to that effect) appeared on display.

As the hill flattened out, power dropped to ZERO and the engine died. This is a very narrow stretch of road with no shoulder and the best I could do to get out of the lane of travel still left the rig halfway in the right lane. I immediately tried restarting and the engine shook terribly so I turned it back off. I thought, "I'll just call Good Sam". WRONG. Cellular said "No Service"! (This is what might be considered a Worst Case Scenario). After about 5-6 minutes of scratching our heads, I again tried to start the engine, and it idled with no problems. Also, the Wrench icon and "Reduced Engine Power" message disappeared. However, the Check Engine light remained on. We continued with no problems for about 20 miles, stopped for lunch, then when we restarted the engine, the Check Engine light had disappeared. No other problems thereafter.

I have NEVER had this happen before. Am I mistaken to believe that the Electronically-controlled transmission should NOT have allowed a downshift to 2nd year in an attempt to maintain the set speed of 45 mph, resulting in excessively high RPMs? Can anyone explain this? It has really shaken me up and, in the future, I plan to actively monitor my transmission when on a downgrade, with my Cruise Control OFF. Did I damage my transmission and/or engine for this brief moment? It would seem to me that, everything that transpired, happened in an attempt to protect the engine/transmission. At this point, am I still covered by the Ford Warranty? Again, the truck is 4 yrs. and 4 months old with 55.600 miles. Is there some recall or Technical Bulletin that addresses this issue? I'd appreciate anyone's wisdom on what happened. Thanks in advance!

Tow Vehicles

34 Replies

ReneeG
Explorer
Jul 14, 2016
DH doesn't use cruise control when we are towing. He prefers to be in full control at all times, just his preference. And since he taught me how to tow, I follow his directions.
SoCalDesertRid1
Explorer II
Jul 14, 2016
dodge guy wrote:
Yep, that is what I expected. You have to control the truck on the downhills. Glad there are no problems.
Amen.
dodge_guy
Explorer II
Jul 14, 2016
Yep, that is what I expected. You have to control the truck on the downhills. Glad there are no problems.
ParkCountry
Explorer II
Jul 13, 2016
I took the truck to my mechanic and it only showed ONE code: Engine Overspeed (tell me something I don't know). That's it. No code on the Tranny. Nothing. I guess, No Harm, No Foul.
BenK
Explorer
Jul 12, 2016
Agree...Am always amazed on these discussions of HOW2 manage an
"automatic transmission" and then wonder why you folks didn't get a manual tranny...

The Tow/Haul is an enhancement that tells the 'automatic transmission' that there
is a load on it, or it is towing something...so it will make different decisions
on HOW2 shift and protect itself

The engine computer and the tranny computer can both set off anyone
of several levels of 'Limp Mode'...which is to protect itself from
the driver and/or conditions

"Limp Modes" as in plural...so ask if it seemingly lost power in stages
from the first level down to the point where it killed the engine...

Cooling down will get it going again and depending on which level of
Limp Mode it went into...it may NOT allow full 'Power Mode' again till
the computer(s) are reset

SoCalDesertRider wrote:
Heavy trucks and their drivers have been going up and down steep grades for many decades, before 'tow/haul' was ever invented, or cruise control too.

Use your brains folks, the computer can't do everything and it can't foresee that sharp turn coming up, that stranded vehicle barely on the shoulder, that fast motorcyclist zipping towards you carving up the turns, that wet or icy spot in the lane, that sudden gust of side wind, that slower moving truck you're approaching fast from behind, etc, etc, etc.

Use your gears and brakes, and most of all, your eyes and brain.
IdaD
Explorer
Jul 12, 2016
thomas201 wrote:
Besides, where do you find a steep mountain that has a continuous 45 mph?

Long and steep grades at that speed or faster are really common out west. Come out for a visit sometime.
GoPackGo
Explorer
Jul 12, 2016
I have a 2013 F350 dually diesel. I full time and have driven up and down many of the 'hills' in Wyoming, Colorado, California, etc. I sure do not claim to be an expert.

I use Cruise all the time but never going down a steep hill - or any hill where I think I may exceed my cruising speed by more then a few MPH. I actually do not see how that's possible because Cruise kicks off the instant you touch the brakes.

I usually adhere to the rule that says you go down in the same gear you came up in. Depending on the grade, I may go over the top in 4/5 or in 3/4. The trans will shift down (as intended) if you press the brake pedal, unless the computer decides that shifting down would result in excessive RPMs. I have seen the RPMs touch 4000 several times. That is when I will get on the brakes until the rig is slowed down a little. Have never seen any warnings.

I agree with the others that you just cannot blindly stay in cruise on the steep downhills. You want to go over the top slow in a low gear to give yourself some margin for the speed to build. Know how long the downhill is and if there are curves. Pick your starting gear and know what's going to happen. Use your brakes sparingly but use them when needed.

I may have to experiment with the transmission's 'manual' mode as this may give me better control.

* I turn on Tow/Haul before I hitch up in the morning and don't turn it off until I stop for the night.
SoCalDesertRid1
Explorer II
Jul 12, 2016
Heavy trucks and their drivers have been going up and down steep grades for many decades, before 'tow/haul' was ever invented, or cruise control too.

Use your brains folks, the computer can't do everything and it can't foresee that sharp turn coming up, that stranded vehicle barely on the shoulder, that fast motorcyclist zipping towards you carving up the turns, that wet or icy spot in the lane, that sudden gust of side wind, that slower moving truck you're approaching fast from behind, etc, etc, etc.

Use your gears and brakes, and most of all, your eyes and brain.
thomas201
Explorer
Jul 12, 2016
Flatlanders. At some point if the "hill" is steep enough and the load heavy enough, the engine will not hold it back. You gotta use the brakes. Otherwise the diesel will scream and cross the redline.

I have driven loads of coal and oilfield junk. I don't care if the engine braking is by Jacobs, a retarder or the variable vanes in my 2012 Ford, you need to help it some with the brakes.

Besides, where do you find a steep mountain that has a continuous 45 mph? I normally see 50, 45, 35, 25, and even 15 mph turns. How do you not use brakes and cut out the cruise control?
Sport45
Explorer II
Jul 09, 2016
The warning lights didn't start until after the OP switched off cruise control and took matters into his own hands. I wonder what would've happened if he'd let the truck control itself running down the grade.