Quick Bird

I just rebuilt my motor with pistons rods heads cam and put a yank ss3600 and I believe there is a problem with the trans, if I am in drive and go WOT the car will start pulling till about 4000 rpm and then it feels like it bogs out hardly pulling till it reachs about 5500.

Only does that in drive but if I manually shift the car it pulls normal thru all of the gears without any problems. Its still the stock tranny and gears. Please help if you know what it could be. Thanks