My truck is a 1992 F150 XLT, 351W engine, 3.55 diff. There are about 155,000 miles on it. It has the factory tow package.
I've had the truck only a few months and it was running great. I tow a 15 ft travel trailer which weighs about 3500 lb. I only tow to the Oregon coast, about 75 miles one way. I made one trip in mid summer, temperature in the 90's, with no problems. A few weeks ago we decided on one last trip to the coast. It was a cool, rainy day. As we neared the town of Florence on the coast, we hit heavy rain with some standing water. I heard a very brief squeal from under the hood and guessed water may have splashed onto the serpentine belt.
We drove through Florence with no apparent problem with the tranny. A few miles north along the coast route 101, I dropped the tranny to 2nd gear on a slow, slightly uphill grade. Well the tranny made a Loud noise (can't describe it) and the truck came to dead stop blocking the highway. There were no gears forward or reverse, the engine would rev but no way would the truck move.
It was quite an adventure getting my truck AND trailer back to town! Thanks to AAA with RV and extended miles coverage, the tow didn't cost me anything. We did have to wait nearly 4 hours for a truck since it was sent from where I started on the other side of the coast mountains.
The next morning I tried the truck this time it had reverse only in both the R and the first gear positions. I had the truck towed to a transmission shop (highly recommended). A few days later I went into the shop and they showed me the tranny pan. It had at least two cups of metal shavings in it! The transmission gears and other parts were totally jammed so they could not even be extracted from the case. ALL internal parts were shot as well as needing a new case. To make things even worse, the transmission oil cooling coils in the radiator were plugged so bad the radiator had to be replaced. They were able to flush out the factory oil cooler and reuse it. I said a few nasty words to the F150 gods. The mechanics couldn't tell what had caused the tranny to self-destruct but it apparently was the original tranny and maybe overdue for trouble.
I had them rebuild the transmission in a used case using all upgraded parts. The itemized parts list is two pages long. I had them put in a heavy duty, two clutch-plate lockup converter, a new radiator, new radiator hoses and thermostat, and a new rear main seal on the engine.
The whole job cost $4200 which was nearly what I paid for the truck! The truck seems to shift fine now. The new converter locks up with a sharp snap. Hopefully, I won't have to worry about that part of the truck as long as I keep it. While overheating didn't seem to be the direct cause of the problem , I am thinking about adding a transmission temperature gauge.
Just thought I'd share my adventure, hope no one else has to repeat it! Merry Christmas to all. ( I wonder if Santa's sleigh is a Ford??)

 

Ouchies! That is quite a tale. I suspect a previous owner put that transmission through heck. A trans. fluid temp gauge is highly suggested as well.

$4200 for a heavy duty rebuild...............another ouch!

 

The shop that rebuilt mine said the average life of these Trans is about 150-170 thousand miles. The 2 I've had went about 165,000 miles. The later ones, 95 and up had several upgraded parts and seem to last longer.

 

198k on mine. No rebuild yet. I say yet because I know it is going to happen eventually.

 

Yikes! Hopefully that one lasts you a long time. I have a 96' with 209,000 on the original E4OD, I'd be lying if I said I wasn't worried about the old trans...Change the fluid & filter every 50k and mostly drive highway but auto's are a bit of a black box for me "fear of the unknown". Shifts great & there's never been much on the pan magnet so I just keep truckin'