Transmission line leaking and pan ID help

[CCiatteo]

I am getting ready to change the transmission fluid for the first time on my 2004.5 Ram 103K (new to me at 90k) and while under the truck noticed a few things that raised a few questions. I found the thread on how to do the change, pull the line, run 18-20 quarts through after changing the filter and installing a drain plug kit. My truck already has a finned aluminum pan with a drain plug and aftermarket temp sender. Do I have pull the rear line to cycle the old fluid out or can I use the drain plug? Any idea whose pan that might be and does it look larger than stock? I bought 24 quarts of Castrol ATF+4 on sale for $4/qt, so I think I should have enough?

Second, while under the truck I noticed the front driver side frame horn was wet, and found this: I'm questioning if the brass colored fitting is factory, because I don't see a similar fitting on the other line? I am guessing these are the push connect type fittings. If I can determine if that's a factory fitting I think I will just replace the line and service the transmission all at once. Could it be an inline check valve or something like that?

I don't have any real history on the truck so I can't offer any insight in that regard. The truck drives fine and shifts fine, so this is purely a preventative maintenance move.
Looking to avoid multiple transmission fluid baths, if possible.
Thanks

 

[JBallou]

The brass fitting is the check valve. It could have been drilled out, and put back in place. The best thing to do with your situation is to splice in a fitting and a new section of hose where it is. First to solve the leak, second it would be a great area to service the fluid from.

 

[cerberusiam]

The brass fitting that is leaking contains the drain back ckeck ball or a place for it. It is just a union so it may be loose and causing the leak.

You should drop the pan, chnage th efilter, and che3ck for any suspicious material in the pan. Chekc the pan is part of the service and why the pan needs dropped. Then as you fill you can pump the rest of the fluid out thru the rear cooler line to exchange it. Dropping the pan and loosening the VB will only net about 1/2 the fluid and service should include a full exchange.