Taco 2x auto trans won't up shift

Just started reluctantly up shifting. Checked the ATF level -its full. It is getting worse by the day. I used to be able to coax it into top gear. Now it won't.

Any suggestions?

Thanks in advance,

Haasman

You didn't mention the year of your truck, is it still under warranty? If yes, get it to the dealer for repair or adjustment. In any case you need the advice of a transmission specialist. If no changes have been made to upset the shifter linkages or the transmission to engine switching you probably need some internal repairs. Sorry I cannot give a specific answer. BTW, welcome to the forum.

Clifton