Wont shift into overdrive
 

So i have a 1996 f150 with the e40d my truck will no longer shift into overdrive when on the highway itll go like its starting to shift then revbomb and I have to wait about 5 seconds for it to shift back down i know its overdrive because if I hit the OD button it doesnt do it just revs reallyloudly my Speedo is messed up anything after 45 mph it just bounces but was never a problem before does anyone have any ideas why im suddenly plagued with this problem