y 1999 Dodge Ram Cummins Turbo Diesel Automatic has 114,000 miles and the transmission has never been serviced. I have never towed or hauled with this truck. Right now my transmission is sticking before it shifts into the next gear.

When driving, I have to rev up the engine and let off the throttle, then gently throttle up again before it slides into the next gear. If I change the high speed shift sensor and the transmission is still sticking, what is my next approach? Since the transmission has never been serviced, would a new transmission filter fix this problem?

Thank you all in advanced!!