Towed my friends trailer (6700lbs) about 80 miles to his property no problem truck ran great. Got to the property had to go to 4x4 to get up the hill to his lot about 1 mile off the main road.

Got to the top to positioned the trailer and noticed a trail of oil between the tire tracks. Looked under the truck and saw fluid coming out of the inspection plate area at the bell housing. Immediately shut off the engine. Found it was trans fluid.

Started the engine and checked all the lines looking for leaks or pinholes, loose connections etc -- nothing, just oil coming out of the inspection cover port. Killed the engine. Popped the hood checked the fluid level and everything was OK. Disconnected the trailer took it out of 4x4 moved it about 10 truck lengths to get ready to get it to the main road for a tow.
Had some extra fluid with me getting ready to 'pour and go'.

Here's where it gets interesting:

After moving it, there was no oil trail. No more leaking. Checked the tranny fluid again wondering if it was out or low and level was OK. Truck was on level ground.

What happened? Is there a pressure relief valve in the front of the trans or torque converter? I know in 4x4 mode the electronics lock the tranny down with higher pressures to keep it from slipping that's my only guess.

I was told if the tranny is overfilled they'll purge out - does that sound right?

Truck ran great all the way home no problems. Checked the fluid again at home and it's OK.

Any ideas???

 

If the tranny gets hot the front seal will leak and puke tranny fluid. When it cools the seal usually reseals.

Were you working her harder than usual?

 

Yes, pulling the trailer up the hill in 4x4 mode. It was about a 45 degree pull for about 1/2 mile.

 

That will do it. If the leak has stopped, I'd say you are OK for now.

 

just add a additional cooler or a larger one or both, my offroad ford used to do that all the time when i first started wheeling it, 4 low and large tires crawling all thru the woods, and it would start puking out the front seal. added a 2nd cooler, and never had the problem again.

 

Mine used to do that junk all of the time. I do NOT miss the automatic at all.

 

Thanks for the info.
Got a cooler to install this weekend.

 

There is no pressure relief anywhere on the trans or torque converter. And no, it does not raise the pressure in 4x4. The pressures are unaffected when shifting to 4x4. Why would the trans need more pressure in 4x4? That doesn't make sense.

That is possible. Most likely with the 4x4 at low speed and the positioning of the trailer you overheated the torque converter. This gets the torque converter hub seal (sometimes called the front seal) very hot and that makes it soft. It then leaks. Once it cools off it seals again.

 

my buddys 99 did that and he had a crack in his converter then it stopped and then it would do it sometimes

 

I would have to say you most likely overheated the trans some going uphill for such a distance. You probably just shot the fluid out the overflow...I had the same problem and I did was top it off with fluid and was on my way. If you are nervous I would recommend changing out your trans filter...you could replace it with a frame mounted trans filter so you don't have to replace your gasket everytime you switch it out.

 

If you still have the original hard gasket it's reusable

 

Read What Mark said. Happened to me and my Buddys trucks after cooling off no more problems. Just add a extra oil cooler.

 

Overflow? Transmissions don't have an overflow. The fluid went past a hot, soft seal, not out an overflow.

The stock gasket is reusable. Don't use the cork gasket that comes with a new filter, it will leak.

If I read what you wrote correctly you are recommending leaving out the internal filter and installing a remote filter. That's a sure way to have transmission problems! Without the internal filter the pump isn't going to be able to reliably pick up fluid from the pan. That will destroy the transmission.

 

Actually placing an external filer does not remove your internal filter. It takes the fluid that has passed through the trans and is on its way back to the pan and passes it through a much higher efficiency filter so as to keep all particals even smaller particals than your internal filter would catch from making it to the pan. I wouldn't take off the internal, but having a filter on the external side that will do a much better job will keep your fluid much cleaner. This no more dangerous than installing a bypass kit from Amsoil for your engine oil. All in all it sets the bar even higher for keeping your oil even cleaner...which leads to longevity, not problems.

 

Also, the unit I have has a pressure bypass in the event the exterior filter is plugged or is not allowign full flow...it will cause the fluid to bypass the exterior filter alltogether... You can check it out for your self... www.dieselsite.com.