2006 F150 5.4 Towing Difficulty

[Tuco]

Morgans fix is the cheapest of all, but morgan, you are asking a guy that installed a tuner to slow down...ummmm.

[J. Morgan]

I got ya,,,, but MOST steep uphill pulls don't last that long and then you can get back on pace!

[Airrogant]

You've already done a good job checking out many of the obvious possibilities. What if the problem is with the code in your tuner? I'm not very familiar with the Edge product that you are using. Nevertheless since it is a tuner, and it is changing your engine's factory operating parameters, I think the first thing I would do the next time the engine overheats is to pull over and reinstall the factory tune. If the problem goes away you have a likely suspect.

I checked out a video on the Edge - what a cool product. I think I might put one on my Xmas list.

[Al and Missy]

I tow between 55 and 60, really. I got the tuner for a little more low end HP and torque.

On the basis of the engine temperature gauge being dead center, I don't think engine temperature is the problem. I read in the shop manual that if cylinder head temperature gets too high the engine goes into an emergency cooling mode where it turns off fuel to selected cylinders and "pumps air through" to cool the engine. No mention of the fact that compressing the air generates heat, but I guess that is less than heat of combustion. That may have been what happened and created the rough running, but it is supposed to also turn on the MIL and set a code which it did not. The curiosity is that other than the rough running and noise there were no other symptoms. No lights, no boilover, nothing.

In three weeks we are headed out and will be going through Asheville on I-40. I think there is a significant grade on this side. I'll be prepared with my IR temp gun and may try dropping back to factory tune if I have a problem. It would be strange if a towing tune made the truck tow worse. For sure I'll stay in the right lane so I can pull off if I need to.

Right now I'm leaning toward Tuco's advice to replace the transmission cooler. ATF at 230 is the only temperature that anyone has expressed concern about.

Al

[jcl]

Originally Posted by Al and Missy

On the basis of the engine temperature gauge being dead center, I don't think engine temperature is the problem.

Engine temperature may or may not be a problem, but you won't likely know anything from the factory temperature gauge. As noted above in posts 2 and 4, many modern temperature gauges are buffered. They are programmed to stay at exactly dead centre for a wide range of actual engine temperatures. They function as idiot lights, all OK unless it is really bad, then it goes to full over to the right. I have had four vehicles now with this type of temperature gauge. My issues were related to the fact that they went to 12 o'clock long before the engine was at operating temperature based on independent readings. If you want to know the coolant temperature reading get an aftermarket gauge.

[ggoat!!!]

Again, even if you have a PINPOINT leak you will DRASTICALLY decrease your boiling point no matter the coolant to water ratio. I've BEEN there.

You can check that very easily. Go to any autoparts store and ask to use their pressure tester; you can use it in their parking lot or you can rent it for free (with a deposit). It is simple to use; all you do is remove your radiator cap, and the pressure tester connects to wherever your radiator cap connected (radiator, coolant tank, etc.). You then apply pressure (it is simple to use) to your system up to whatever PSI your system is rated at (probably 15lbs; it will state on your cap, hood, or on your engine literature somewhere). The pressure tester has a gauge on it and all you are looking for is the ability to hold pressure while simultaneously looking over your engine for ANY signs of coolant seeping out. I found a BUNCH of spots on an old Dodge Caravan that way...it is free to check, and the only SURE way to rule out a leak in your system.

Just because you weren't leaking coolant (that you could see) or that nothing was steaming does NOT mean you can't have a pinhole leak somewhere causing coolant to boil prematurely IN the system while NOT leaking out somewhere. This creates airpockets in the system that form HUGE hotspots causing loss of power, crackling, gurgling, and popping...and, depending on where your cylinder head temperature sensor and coolant temperature sensor are in the actual system, sometimes your gauges may NOT show an actual elevated temperature...due to the air pockets in the system.

I fried the engine and transmission in that old Caravan going up a huge climb (no trailer) from Strawberry to Pine, Arizona years ago when the plastic stopcock broke in my radiator and I lost ALL my coolant...but I had NO idea until it was too late. My coolant temperature gauge showed NO overheat condition because there was literally NO COOLANT in the system to actually measure the temperature of. My only clue was sudden loss of power and loud pinging...and of course engine destruction. This same thing can happen when there are air pockets in your coolant system; i.e., the gauges won't necessarily show an overheat condition.

The excessive heat blew not only the head but also the transmission about a week later because if your engine gets super hot so does your tranny since they are connected together not only physically but also the transmission fluid flowing through the radiator...and heat KILLS auto transmissions. 230 is toooooooo hot for a transmission.

I've been down this road...

[J. Morgan]

I don't know if I would replace or just add another in series.

I guess that would be situational though, depending on space available, configuration, line route, etc...

[Al and Missy]

I found a web site that will deliver a build sheet for Ford vehicles from the VIN.

Go to https://www.etis.ford.com/vehicleRegSelector.do

Under the VEHICLE tab, click the VEHICLE SELECTION tab. Enter your VIN. Click VEHICLE SUMMARY. On the right side of the page will be a list of the major features of your vehicle. At the bottom of that frame will be a link "There are more minor features for this vehicle, click to expand this list." Click this to get a complete build sheet for the vehicle.

Here are all the towing-related features from my truck.

Vehicle Line:F150
Body Style Double Cab (3/4 Door)
Engine:5.4L 3V V8
Transmission:4 Speed Automatic 4R75E Livonia
Drive:LHD 4WD (PTD)
Axle Ratio:3.73

* With Base Payload Package
* 150" Wheelbase
* With Heavy Duty Trailer Towing
* H/D Dual Front Shock Absorbers
* Heavy Duty Rear Shock Absorbers
* With Super Engine Cooling System
* 3.73 Rear Axle Limited Slip Differential
* With 9.75" Axle
* 5.4L 3V V8
* Heavy Duty Aux Trans Oil Cooler
* 4L34 5310 VA Left Front Coil
* 4L34 5310 VA Right Front Coil
* 6L34 5560 ME Left Rear Leaf
* 6L34 5560 ME Right Rear Leaf
* 4 Speed Automatic 4R75E Livonia


Don't think it is missing anything that would help with towing,except the HD payload which wouldn't help with the trailer, but would let me carry more stuff in the truck.

I'm seriously considering adding an active transmission cooler, and will be more diligent about controlling transmission gear on the way to Falluminum.

Al

[ggoat!!!]

Have you pressure-tested your system yet as I described above?

[Al and Missy]

75th,

No, but I will. We have had guests almost since we got here and I just haven't taken the truck anywhere. There is a Autozone about 10 miles from the house. However, as I posted a few posts back, my tuner records the highest values seen for a set of parameters. While the high temperature for the oil and cylinder head was in the 230 degree range, the coolant temperature max was 218. So I'm not expecting to find a problem.

Al