P0734 BMW -

Question

2000 BMW 528i, 266k miles...speedometer, gas gage, mileage counter stopped working all at same time. ABS light and engine light is on. PO734 4th gear incorrect code. Car drives okay, then when gets to fourth gear, seems like something is mashing down on the transmission then a hard clunck. A swiggly circle with a dot in middle, light comes on. Then seems like the transmission is dragging but still drives. When shut car off and start it up again, light is gone swiggly circle with dot in the middle light is gone and car drives normal until the incorrect 4th gear shift happens again. I was told I need a new ABS system which cost $2100 for labor and parts. Need to know if this is the problem before spending all that money, and car problem is still not resolved.