Vibration in 4th gear?

[Twin Pinzies]

(And when I say 4th, I mean the gear that is far right and up with the shift lever.)

Hey guys, I've noticed recently that when I shift into 4th, there is a noticeable vibration in the drivetrain. All the other gears are smooth as a prom-queen thighs.

Any thoughts?

[Jim LaGuardia]

Check and lube u joints, next drain trans and check magnet. If it is fuzzy with metal bits the trans needs attention.
Power flow for 4th gear is input shaft drive gear to front lower gear set transferring load to 4th drive gear on lower gear set to 4th driven gear at front of main/output shaft. There is a pilot bearing between the input and output shafts that can also fail and make noise at times under load. The load on the bearing is highest in 4th gear.

[Twin Pinzies]

Thanks Jim!

You are the man.