You can display the transmission temp and the engine temp all the time on the 8" LCD cluster shown with a simple FORSCAN change. Link below.. The first of many changes I made. Really nice when you're pulling a trailer to see both the engine and transmission temperatures. FYI - I pulled a 7000# trailer cross country and my tranny temp hardly moved from 205 (which is where it sits when I don't pull a trailer). Did over 70 almost all the way...

https://docs.google.com/document/d/1...gF1wxIqxY/edit

 

Temp display after Forscan changes:

 

Actually, it's a great interface, because you correctly assumed what it was trying to tell you. 237 is getting quite hot. If memory serves, you'll get into warning messages and reduced engine power at 240. It's not unheard of to be in this territory if you're towing heavy, but you should never get there unloaded.

Just for a data point, I have mine set to display all the time and even during a hard code 3 run during Texas summer heat where I'm absolutely ragging on the truck, I've not seen temps north of 230.

Have your phone ready and shoot some video if the temp spikes again, then take it back to the dealer.

 

Thanks for the data point.

I was going to pay a bit more attention to boost levels and temp on the way home. I'll try to play with the gear lock out as well. I've done a few forscan mods but I don't have the adapter with me - just a cheap obd2 adapter that I'm logging with torque.

 

Alright - so I had 11 hours to figure out what was going on. From Taos, NM -> Dallas, Tx.

Leaving at 2am (yea, couldn't sleep), I could not hold 65 thru the hills. It would easily hit 230 at the peak. It was in boost up the hill, then leveled out, heat soaked, and cooled back down to what I expect was about 219. My co-pilot was asleep, so I don't have exact numbers.
Locking out 9/10, it did better. It also cooled pretty quickly, but it was only 15 degrees or so.

I played w/ this on and off thru the hills. It was really dark, so I didn't get any video.

Fast forward to about 8am, and I'm around the outskirts of Amarillo on fairly flat land. I could not hold 78MPH in 10th gear w/o hitting 230 on even the slightest grade - and this is an Amarillo grade, so basically flat. Running at 77 MPH in 8th, and i stayed out of 'digital display'. My copilot finally woke up, and we were running around 219-222.

I let it cool down at home and hooked up Forscan. Idling in the driveway with full heat, it was sitting at 194 which seems about right. I went on a test drive in the city, and staying under 50MPH, I got the temp to 219 which is where it stayed for the most part.

I popped the coolant reservoir cap and let it idle for a while w/ full heat hoping it would burp some air out. Not so much. I'm not sure how to verify the appropriate flow (to rule out a blockage) vs. a bad water pump.

I guess I'll go talk to the dealer that did the VCT work. In theory. this is new coolant and oil w/ ~4k miles, so fluids should be in good shape. IDK what else to check. And it still starts cooling when slowing down - so the system seems to be 'working' -- just not very efficiently. The front grills doe appear to be open. I can start tracking that in Forscan going forward.

I did determine the following on the gauge. The following observations assume you draw a line straight up from the left side of the temp symbol flag.
Left of the line < 230
On the line 232-234
Right of the line a couple of pixels/columns is 240
It does start to move a bit more per degree change above 234.

Also - I lose heat when digital temperature comes on, so that tells me one of my initial hopes that this was just a random threshold that was there. Something is definitely amiss.

 

You should have no problem maintaining those speeds with a fairly significant trailer behind you. You certainly aren't climbing any real mountains or anything.

You could try unplugging the grille slats just to see if that makes a difference, but I'm betting you've got air in the system, a thermostat issue, or something more sinister going on.

 

Yea - I've done this trip before, so I know this is not normal. I may try the rev & purge that FordTechMaculoko talks about in It's not Eco specific, but...

 

So I got my truck back from the dealer. They were unable to reproduce the problem even after taking it home/round trip of 100 miles. I spoke w/ multiple advisers trying to figure out what to do next.

I left the service drive and immediately reproduced the problem. I went back to see if maybe a tech was available for a ride-along -- no such luck on NYE.

I figure I have 2 options - try a new dealer, or continue to work w/ this one since I am quite confident this condition is due to the previous repair they did. I guess it shouldn't matter since I am at 48k miles, and well within the 60k powertrain (assuming cooling issues is covered under powertrain?) and I also have the Ford Premium Warranty.

The scenario appears to be a heat soak condition - accelerate up a hill (on ramp) keeping the truck in boost as long as possible, peak at 70-75 MPH, release throttle, temp spikes to 232. 55F ambient temp. It was just me in the truck w/ 1/4 tank of gas. Running around town seems to be 212-219 which they claim is normal.

This varies greatly from the above data point.

 

Have you had the Tranny checked? In the older cars and trucks the tranny would cause an overheat just as fast as an engine. You sy downshifting and locking out the overdrives helps. What about speed? Do you have a separate tranny cooler or just the stock one? I think I would start looking at the tranny and fluid to see what might be up. Just Swagging

 

Interestingly, I was driving back to Texas from Oklahoma, unloaded. Running 75-80 mph, my temp gauge started displaying actual temps several times. It would go back down, but I can’t think of any reason for it to get hot when me and a small suitcase were the only things in the truck. Plus, it was probably 40-50F outside. I suspect the front radiator air dampers were not open enough...or not opening quickly enough.

I’ll be interested in what others have to say about possibly root causes. I only have 58K miles, so I wouldn’t suspect that a coolant change is needed yet.