G54 stuck in gear

[manfredo]

I have a 1989 d50 g54 that is stuck in 1st gear.
oils is good and nothing out of the ordinary; not burning smell or grinding.

I'm going to follow the repair manual in the next couple days but does anyone have any ideas on what to do first?

[geezer101]

Is the gear selector free? Like stirring a stew pot but nothing is engaging? If the selector bush has worn out or straight up disintegrated or the selector lever housing isn't screwed down, the selector lever can pop out of the linkage and drop the selector fork out of it's cluster. If that is the case you won't need to pull the gearbox apart to fix it. You should be able to manipulate it back onto the fork and re-engage it. You'll feel it, just takes patience to figure out where the selector rods are going. You will need to do this with the gear lever off the gearbox so you can get to the selector linkage and jiggle it around.