Draenor
KILL ALL HUMANS!!!!
Remove ur linkage and try shifting it with your hand if there is a lot 1/2 inch of play that is most likly the problem?
And as a side note ive have never heard of a th350 tranny shifting on its own from 1st to 2nd if you manualy have the shifter in 1st? The th400 will.
And do you have your kickdown cable hooked up? Or does it even have a kickdown cable? Even if you're not using the kickdown its a good idea to at least have it hooked up in the tranny or it will do all kinds of funny stuff.
This.......