I have a 90 f150 with 351w and the e4od trans for a while now the trans has been leaking tranny fluid only under high pressure situations, for instance the 2 times that always come to mind is driving at 70 on the interstate it will leak so bad after a little time it looks like the exhaust has caught fire under my truck and after stopped to check nothing is leaking at idle this happened again backing a boat up a hill it started pouring out, looked like the front seal had blown but put it in park and let sit for 10 min no more leaking. I have also driven down the road at 55 after these problems and checked and only a drop or 2 from the leak is there. I am severely puzzled as to how it can leak then not leak and to why it seems to be making that much pressure to leak. Any help is greatly appreciated, i dont know much about transmissions and cant really afford a mechanic.

 

I would honestly start off by pulling the trans out and replacing the seals.

 

Where is it leaking from? The pan, or bell housing? An unlikely possibility is its overheating and just venting. Your cooler could be clogged causing it to not flow well and overheat.

 

All the seals are good in the trans doesnt seem to leak unless its building a lot of pressure and the fluid looks like its coming from inside the front of the bell housing, i dont have a seperate trans cooler eigther the lines hook to my radiator wich was brand new a year ago. I had thought about the overheating being possible would a seperate cooler help it run cooler.

 

These transmission are notorious for running to hot. This is the tranny I had on my 91 bronco. The good news is that 2 fairly easy things Can make this tranny have a long life span in my past experience. I had a transgo stage 2 shift kit installed which is about 1 hrs. Labor in a tranny shop. Or if you want you could do it yourself after watching a video tutorial. Next I installed an aftermarket 24k lbs cooler with a 10" fan. I wired a thermostatic switch to the battery and when it got to 180degrees or more it would automatically turn on the fan. I also installed an override switch in the cab and whenever I went off road I just turned it on manually. Rock crawling, hill climbing or just plain slow going. I traded my huge bronco in at 178k mile. It still had the original tranny no rebuild. Usually these trannies only go about 100k or so due to overheat and slippage issues. As far as the seals themselves go they could leaking due to over heating or of course overfilling would also cause fluid to purge out the seals or overflow. Good Luck and God Bless!

 

Yea, because even with the tow package the transmission cooler is too small, I still need to get a bigger one. Fluid coming from the bell housing normally points to the front pump seal. Mine went out after getting stuck in mud, it would leak whenever I was running the truck and it warmed up, but would stop after I turned off the truck and it cooled off. It didn't leak when running cold. When it did leak, it would leak about a quart every 3-5 minuets, it was a crap load.

 

And my friend with a 97 7.3 with the e4od has 320,000 miles on the original tranny. They can go for a long time if you put a good cooler on them.

 

have you checked the trans fluid? Is it at level? Could be too much in it (overfill) or as other stated, could be overheating and coming out the vent

 

Thanks for the help guys sound like its overheating il try a trns cooler it just hooked to the radiator now will it make my truck run hot since itl be infront of the ac compressor and radiator

 

Not that I noticed, but then again the electric fan came on at 180deg on mine. I installed had an off-road ADS superchip tune in mine though with 160 thermostat and octane bar in the distributor.