A 518 Tranny problem no go when hot, what's the deal?

[chargerbr549]

I just bought a 92 Dakota 318 4wd and I believe its the A518 and not the A500 although I haven't looked underneath yet. The tranny seems solid and works fine when its cold except it wants to shift later than normal kind of like the governer is maybe screwed up but when it gets hot sometimes you will completely lose function in forward gears and reverse and sometimes messing around with it it will momentarily engage reverse, but then if I let it cool off for several hours it will function in forward and reverse again. I checked the fluid level and its ok and the previous owner changed the fluid level not too long ago, my thinking is maybe there is a valve sticking in the valvebody. Has anybody else ran into this problem?

Kevin

[flyinlow]

I remember reading about bad check valves in the cooler lines. Blocked the flow, caused problem when trans warmed up and eventually failure. Might check the flow to the radiator/cooler.