96 Bonnie - Transmission issue..

A while back I had the transmission serviced in my 96 Bonnie. Since then I have noticed that the overdrive doesn't kick in until around 55 - 60 mph. Once in overdrive it is very touchy. It doesn't take much to get it to jump out of O/D and back into Drive. This is killing my gas mileage. Can this be adjusted somehow or is something on its way out? Ant help will be greatly appreciated. BTW - 180K in mileage on the car.

Thanks Much,

Geno

Welcome to AF, I would start by having it scanned and look at tps and calculated load readings, both can cause what you have.