ok, i bought a used manual tranny out of a wrecker about 7k miles ago, and i figured it wasn't perfect, i just didn't have money for a rebuild. ok, here's the problem.

you know how the shifter has play from 1st to 3rd gear, so if you barely move it, it moves back and forth? and if you push it all the way to the left, you can shift to 1st or 2nd, and if you push it all the way to the right, you can shift into 3rd or 4th. if you push it to the right with force, then you can get into 5th or reverse, cuz of how the tranny just resists more so you know you're getting to 5th gear.

ok, well when i'd make long 2 hr drives, when i shift out of 5th, and go for 4th, the shifter has play all over the gears. i don't have to push it hard to get to 5th like normal, it just moves easily like between 1st and 3rd. this isn't a big problem, but i can't get into 4th when this happens because the shifter doesn't stop like it normally does. this goes away after about 10 seconds, and it gets normal play and i can get into 4th with ease. i didn't get too concerned about this the first time, which was a month ago, but now it was doing that just on the city roads while driving for only 10 minutes. it seems like the problem is escalating. is this a bad problem or just a harmless effect? if it is bad, what will happen if i wait, and how long do i have?

 

Sounds like one of the springs in the extention housing at the shifter is binding. There are actually two, one wraps around the control lever and rests against the control rod end, the other, probably the bad one, is inside the change control case. It has a 2" long spring and ball bearing that is probably getting caught. through a small amount of time and vibration, it works itself loose.
Is there oil in the change control case (accessed by removing the shifter inside the car)? If not, I bet filling it up with HD gear oil might solve the problem.

Lars