This is my first post here so sorry if i sound a little noobish or uneducated.

I have a 1999 Ford F-150 XLT, with the 5.4 and a 4spd auto. 172,XXX miles on the clock and i have owned it starting on April of 2014.

Tonight driving home from work, it took some time on the highway (4 miles) to shift into top gear. When you lift off the gas pedal after reaching the speed limit, normally the truck will shift from 3rd to 4th no problem. When I let off the pedal, there was no gear change. It took sometime for it to shift up. When downshifting on the exit ramp, there was nothing abnormal. Where I live it is 19 Degrees Fahrenheit and this is the beginning of the cold snap that will last well into mid-January of next year.

Does anyone have an idea of the issue, and should i for the time being leave my truck alone and borrow my dads?

 

Start with the easy things first. What is the level of the tranny fluid? What is its condition? Is it red or brown. Does it smell burnt?

I always change all the fluids when I buy a used truck so that I know what is in it. You never know the care, or lack thereof, of the previous owners.

I take mine to the shop and have the transmission fluid exchanged with one of the T-tech machines that connects to the transmission cooler lines and let's the truck pump out the old and suck in the new.

 

It's normal!
Reason:
The transmission valve body has a temperature sensor.
Below about 98 degrees the PCM prevents shifting to OD until it gets above that temperature.
Cold start in your temps will do it every time and take some miles to get above min temp.
There is a lot of metal and fluid to heat up..
Good luck.

 

Thanks to both of you. I have a friend who had the equipment and ill take it to him soon. Now for the million dollar answer, is there any way to speed up the heating process? I only live 8 miles from work.

 

Yes there is. Park it in a heated garage overnight.

 

Let the truck warm up a bit before driving and or put some card board over half the radiator. but watch for any signs of overheating and adjust accordingly.
At 23 degrees this evening I drove nearly 5 miles after letting the truck idle, before OD would drop in.
I specifically watched it because of your question.
.
You can monitor the OD function by watching the Tach.
When the Tach stops rising and dropping with light throttle changes and locks down, the trans temp sensor has allowed the PCM to allow OD and TC lock to work.

Your in a catch 22 with this because as soon as you begin to move there is extra cooling due to the cold intake air through the radiator.
.
Remember the Trans cooling lines go through the radiator to cool 'and' pick up some heat when cold so it also has some dependency on engine temperature rise, outside air temp and air movement all acting at the same time. An aux trans cooler also has some effect on delay.
Let us know what you see.
Good luck.

 

WRONG!

The radiator NEVER heats the ATF. Never. In any condition. EVER.

I've tested this in ambients as cold as -40F and as hot as +115F. I measured ATF temperatures in and out of the radiator and coolant temperatures in the radiator around the trans cooler. Notice I didn't say heater, it is a cooler, in all operating conditions. I never found a condition where the coolant near the trans cooler was warmer than the ATF. Never.

You're making a very common mistake, thinking that the radiator is at engine temperature. It isn't, especially in cold ambients.

The trans cooler is in the side of the radiator where the coolant has already passed through the radiator and has been cooled. In cold ambients this means the coolant is nearly ambient temperature by the time it gets near the transmission cooler. Cold coolant will not warm the ATF.

 

Your mis interpreting what I said.
.
Never did I say or assume the radiator coolant is the 'same' as the engine temperature. It cannot be or no cooling is possible. Read as heat loss.
.
The radiator overall certainly does "depend" on the engine temperature via, thermostat opening, fan speeds, road speeds, ambient temps etc..
The conditions very all over the place vs time and physical locations within the radiator.
From a cold start such as described in this thread, the engine temp will rise faster than the transmission temperature as this is where the heat comes from {in the short interval of time both are rising to stabilization.}
The worst interval is between cold start and the time interval up to first thermostat opening point.
It's at this point the circulation of transmission fluid can pick up some heat from the radiator coolant. Granted, it is a short interval of time but that's what is being said for this discussion.
I appreciate all your measurements but are they static or have you done running dynamic measurements from a cold start through stabilization?
I too have extensive cooling system and trans cooling experience all done to be sure hot summer time trans and cooling systems would not be an issue towing at and over GCW.
Sometimes these improvements slow cold temp stabilization of both systems in cold winter temps.
Read as larger radiator, large Aux trans cooler, deep pan, trans temp monitor right out of the converter and temp measurement on each part of the systems.
If you check some sources, they will tell you not to bypass the radiator trans cooler when hooking up an Aux cooler just for this reason.
New trucks are often equipped to automatic radiator cooler bypass systems as well, to assist both systems getting up to temperatures and run cooler in hot temps over a wider range of ambients..
.
The radiator supplies 'some heat' after the thermostat opens the first time, to the trans fluid to shorten fluid heat time in cold temps before (a reversal takes place) in the cooling cycles to support your position..
There is a lot more to these dynamics than meets the eye so to speak.
It's not wrong or a mistake.
Good luck.

 

IM not sure if I'll get told no about this but when this happens to mine ( the holding of a gear) I'll hit the OD off then on really quick, fast enough to not shift down when doing n it usually gets it to shift up , if that makes sense

 

Yes, it's wrong. My testing was all dynamic. There is NEVER a point where the coolant near the transmission cooler is warmer than the ATF. You haven't tested it cold, I have.

 

Oaky doky.
It makes no difference to this situation of cold start to transmission temp high enough to allowing shifting to OD.
Good luck.

 

I do this almost everyday to get it to shift up in Montana winter , Maybe if yall turn off OD Before take off then when u feel your speed is where u wanna shift turn od on ?
My driving style Is i start truck, turn on lights ,turn off OD ,then drive till about 40-45,50 mph theN OD on , not every time when I take off shut OD off for fuel consumption .its worth a try... I think it's time to cook some burgers

 

Well no matter what you do you can't change the way the system works from a cold start.
The sensor on the valve body is electrical.
It's an input signal to the computer.
Turning off OD has no effect because the temperature sensor will not permit it to work anyways until the temperature has come up to near 98 degrees on the valve body where the sensor is located.
By the way the same sensor can report an overheating condition.
Besides this, the OD does not operate below about 45 no matter what you do.
One reason it is designed to work this way is if the converter were to go into OD and Lock up under cold conditions, the fluid pressure is higher due to viscosity of cold fluid and a total lock up of the drive train prolongs heating of the trans fluid to proper operating temperatures.
When the trans is not up to speed and out of Lock, the converter fluid shear generates needed heat for faster cold warm ups.
There is a lot going on to consider between cold start and the time the OD will be allowed to work.
Instead of all those gyrations thinking your controlling this, just get in start up and drive.
The system is designed to take care of it'self.
Good luck.

 

Hmm , so it was -3 just now , I jumped in my frozen truck , drove to the store w/out letn warm up , truck held gear , I turned OD off then on and it shifted up. I like pizza Steve

 

Yep. This is mentioned in the Ford Shop Manual.


(I just cringe when the engine gets up to 2500 RPM waiting for it to shift into OD and I know the engine oil is not up to temp. Another downfall of living on a major roadway.)