Manual Legacy 2.0L jumps out of 5th gear

[grantlar]

Hi, just bought first SubaruLegacy (1999) manual gearbox, and discovered that it jumps out of 5th gear on occasion. Subaru workshop disc says has been a known problem on 1999-2003 cars, yet local dealers deny problem or any knowledge of it. Does anyone know if the loose shaft nut (which seems to be the problem) can be fixed with gearbox in car? Any info appreciated. Thanks, Grant

[SpeedmanRC]

Mine was popping out of fourth all the time and 5th when fast on/off gas and the rear main bearing ate it self to many pieces and was causing it. replace the hole trans with a low milage one. shaft nut sounds like...what one I believe both main and cluster/front drive shafts have nuts on them.

[one bad bg]

sounds like a bad syncro but thats weird that it only does it in 5th, usually theres 1 syncro for 5th and 3rd, sometimes 1st too but im im not sure

[ouch1011]

Bearing wear is the usual cause for popping out of gear because 5th usually sits on the outside edge of the gearset, so it is the one most affected by bearing wear.

You can tear down the trans to see if you can find the cause. I'd personally just replace it.

[Airgne]

its your syncro is gone for 5th. happend to me before. took tranny apart and no 4th gear syncro.