96 geo tracker shifter problem

I have a 1996 tracker 4X4 manual transmission shifter that seems to lock up or gets very stiff to shift gears. I have replaced the tranny oil.
It usually acts up downshifting going from 5th or comming out of reverse.
1st and 2nd shifting is affected most often.
Any help would be great!

I have a friend that was having trouble shifting his 5 speed tranny. He had it looked at and it was a bent gear shift shaft and shift fork. When you drained the fluid did you notice any metal particles or debris in it?