I am new here , new jeep owner, Read all the post before changing my transmission fluid. I was having trouble shifting into 2nd gear and could not downshift. Decided to go with 10W30 Mobile 1 oil in Ax15 transmission ( Per Chrysler recommendations). Now the transmission shifts beautifully into 1,2,3,4 and I can down shift easily. But now it doesn't want to shift into 5th gear after it gets warmed up like half hour of highway driving. it will go in but I need to shift fast from 4th to 5th. if I drop it into neutral then into 5th it wont go doesn't grind just wont go in. any thoughts?