Had this problem for a little while now. I roll under the truck and the bottom of my tranny and the tranny lines that extend up to the radiator covered in reddish fluid. I check all my fluids over the course of the next month and I lost no fluid. I'm a little stumped. There is even a little bit that goes up onto my oil filter. I cleaned it all up and it all comes back but I can't seem to trace from where. I left the cap loose on the power steering fluid awhile ago and lost some fluid but it still can't be that unless it's sitting somewhere that i can't find and then blowing all over the place. Nothing on the ground under the vehicle.
Anyone have any ideas of what or where to start looking. I was thinking the bellhousing because it looks kinda like it's leaking from there, but I can't tell for sure.

 

ATF fluid it sounds like. You might have a leak in one of the tranny cooler lines, check the rubber and the connections first.

 

I was thinking ATF also. I just installed a tranny cooler so I checked the lines there and they are ok. The lines then run back to the tranny cooler in the radiator and all seem ok except for a few drips on the bottom of the radiator but none of the lines or connections seem to leak and the radiator is brand new and no loss of fluid over the course of the last month or 2.
Could a small leak in the lines towards the front of the truck make it all the way back and settle on the tranny pan? Seems like a long way to travel.

 

check the hose clamps on the rubber hose that goes to the AUX cooler......mine had the same problem and a clamp worked its way loose.....

 

Check on them tonight. I still can't seem to imagine how the fluid could work its way all the way back to the tranny.

On a side note, I've been using power steering fluid all these years and I just read that I need to use tranny fluid in my power steering resevoir. Wow I'm at a loss for words. I guess I'll be sucking that out tonight and replacing. Normal Synthetic ATF ok or is there another recommondation on what to use?

After tonight I may not be able to make it back to the forum for a few days so I'll get back to everyone on what i find.

 

any Mercron V fluid in the power steering pump.....

the fluid could run down the lines back to the tranny....the wind would blow it back as your are going down the road....

 

I thought of that I just had in my head that it was a long way to go............and a short time to get there, we're gonna do what they said can't be done.

Name that tune anyone and you win!

Yeah, way off-topic, I believe I've been working to much lately. But this is my 400th post! Been here for 2 years now and about 350 of them were over the past few months. Finally starting to feel like I belong here. Takes me awhile to act myself unless I've been drinking, and i don't do that as much anymore.

 

I did some further checking on this and the fluid is ending up on my oil pan right around the drain plug not the tranny pan.

Checked my hoses one seems a little loose so I tightened it up but no fluid in that area. Aux. cooler lines are good and no leaks. I removed my top connection into the radiator and reinstalled it. This is where i think it may be leaking from, seems like it is the wrong connection for it and it tightens up nice but I think only because there are no more threads left to tighten it down more. There is some fluid in this area at the top of the radiator and at the bottom of the radiator under this connection. Bottom connection on the radiator looks good and no fluid on it.

I'll have to wait and see how it goes. Hopefully by reinstalling the top connector i took care of it. If not i may have to get a new connector. But still no fluid loss when I check it.

By the way I syphoned out the power steering fluid and replaced it with the Mercon V synthetic blend.