I made the mistake of selling my dually a few years ago when wife and I moved from a fver to a motorhome thinking I don't have a big trailer and don't need that much truck for a daily driver.

Fast forward until now.we sold the coach and have downsized to a 24 ft travel trailer.Im towing with my 01 f150 5.4 crew with factory tow package.Loaded weight of camper is 5200lbs(I scaled it)when towing camper the trans will puke fluid out of vent on top of trans case. It's not a lot of fluid ,but enough to leave spots on front of camper and a wet spot on the ground.

I have a factory cooler and I installed a trans temp gauge .It rarely exceeds 200 degrees.

I'm not pressing truck hard on long hills and I always take it out of over drive when towing.Im second owner of truck ,I purchased truck from brother aboit three years back .He purchased it new and used as a daily driver but never towed much with it.so I basically now trucks history.

The truck currently has approx 130,000 and performs nearly perfect except from this problem
Any suggestions other than a bigger truck because budget won't allow that now

 

Fluid level, what is it full normal running temperature as checked with the motor running?
Should be between the cross hatch limits with no over full.
Is you temp gauge in the trans pan or the converter output line?
If in pan, at 200 it's a bit high and may be the clue something is slipping under heavy towing loads.
Max fluid temp is 225 before a code is set. Considering gauge accuracy it may be going too high.
Your total gross combined weight is approaching max. for the truck.

Good luck.

 

Fluid level is basically center of cross hatch with truck warm and engine running.
​​​​Under no load temp will average around 170-180. Towing in level is not much higher,,i've seen 200 a couple of times on long pulls or stop and go traffic.

Had a friend with a trans shop install gauge sensor so I will have to look at where it's located ,I assumed it was installed in the port on side of trans next to shift linkage .

 

Here are my operating conditions to compare to.
Gage is sampling the fluid temp just out of the converter.
It will normally fluctuate over a wide range at a faster rate in relation to trans loading. It can be alarming if you never saw it before but is normal sampling from this line.
Non towing on average road in OD will hang around 148 to 150 in stable driving. Much stop and go will raise the temp.
.
Out of trans converter lockup, pulling a long mountain hill will rise to 215 +/-depending on outside temperature.
Summer temps towing will run it up to 220/230 range.
Remember this is right out of the converter the highest temps you will see due to fluid shear in the converter when it's out of lockup.
As the load decreases the temp drops quite fast.
.
In the pan or side of the trans the temp change is much lower and slower and at the end of the line in relation to temperatures.
The fluid is normally able to go as high as 260 but it enters the breakdown temperature area at this point so change intervals would be much shorter if it is done to frequently.
When you see temps near 200 in pan or case area it becomes a concern.
Good luck.

 

I don't agree with that. If you had said 250°F instead of 200°F I would have agreed.