Mack with 8LL Roadranger troubles

[Olivetroad]

I drove a early 90's DM dump truck yesterday with a 8LL Roadranger transmission that is for sale. When you would shift into any of the top row of gears, if you allowed it to, the shifter would slide past the normal position until it would fall against the heater and dash. The transmission gear itself stayed engaged properly, but the shifter itself would fall out of place and then when you wanted to shift to one of the lower row of gears, you had to search around to find the slot to let you go back to neutral.

Any ideas? I have removed a lot of top covers on these to inspect gear condition, but I have never touched one with a wrench. Does this sound like a problem in the transmission itself or just in the top cover and shifter?

[maxidyne237]

The shifter tower is wore out. I just ran into this same problem on an rt-910 that when shifted into 4th gear would put trans in gear but wouldnt stop and would hit the dash. The shifter would float until you went back into fourth gear. I thought it was in the top cover until I pulled out the shifter. The shifter ball in the top of the shifter tower had worn and the spring had forced the shifter upwards compensating for wear and had thus let the shifter raise its self. (truck has well over a million miles) It was high enough to fall out of the shifter rails when in certain positions, like fourth gear.