I was driving to a friend's house going about 45MPH and my Caravan started slipping into first and second gear. Once the check engine light came on, I pulled over and parked my van on the street. The next day I went back and drove it and it was fine, except that reverse didn't work. I revved it a couple times in reverse and all of a sudden, reverse worked and it shifted into 1st and 2nd gear. A week later, I took a scan tool and it threw out P0700, P0736, and P0736. I took it out for a spin and it drove fine for the first 15 minutes. It went into 1st, 2nd, 3rd, and 4th and downshifted fine. Once the engine is warmed up, it started slipping into 1st gear again, but went into 2nd fine. Today, I started it up and needed to back up into my driveway, reverse didn't work. I jacked up my car and looked at the solenoid pack, it was dry as a bone. Tranny fluid was slowly leaking out of the pan gasket and my cooler lines and radiator is leaking.
Basically do I need a rebuild/replacement or is there a fix to it? If I am going to need a new tranny, should I rebuild or put in a remanufactured one? Is it even worth repairing if I need a whole new tranny? Right now I have no reverse, a tranny that slips once the engine is at operating temperature, I don't know if my faulty radiator has anything to do with the slipping. I erased the codes and the check engine light has been off since then.
Some info about my van:
-3.3L V6
-4 speed transmission
-222000 Miles
-Year 2000.
-Changed tranny fluid @ 50K and changed tranny fluid + filter at 209K.

Thank you!

 

Question, How much do you want to put into the van? If it were me, I remove the transmission and open it up and find out hat broke. But that's me.

 

I think the max I am willing to spend on the transmission itself is around $1000~. I was thinking that if it needed a rebuild, I might just swap out the tranny with a remanufactured one from o'reilly. I moved it for street cleaning 2 days ago and reverse was normal. I was able to reverse up my whole block with full power. Do you think it needs a rebuild? I would open it up but I have no experience with auto transmissions.