driving to christmas the other night down the interstate with myself and family (been on istate 2 mins tops) heard a fairly loud clunk and rpms went way up and had no gears forward or reverse so i coasted to a stop called for a tow the next day i go to show a buddy what its doing and it goes into gear right away so we go for a drive only to find out once we reach 7mph pops outa gear and no matter what you do wont go fwd or rev so i shut off restarted goes into drive but not reverse (it never has reverse) tried driving back home boom 7mph trans popped out again so i restart and drove back home and hooked up scan tool and came up with alotta codes p0740,p0720,p0715,p0732,p0700,p0700 last one p0700 is in there twice but if i rember correctly we bought it with that code showing i live in south dakota it was 10degrees that night i dont even know where to start with this problem the loud clunk concerns me but fluid looks like brand new and the van only has 145000 miles on it its a 2000 with a 3.3 any help would be great thanls kevin

 

All the codes indicate an electircal problem controlling the transmission. I would start by checking all the electrical connections to the transmission.

 

Yoou want to look at the TCM wiring as well, especially the grounds.