Which seal?

[drive2tractors]

Ordered a new rear seal for the T5 gearbox and it looks nothing like the old one. Is it new and improved or do I need to find one of the originals?

new one on right, old one on left. The new one fits both the shaft of the prop shaft and the seal recess on the output.
Any wisdom much appreciated.
d2t

[phillpot]

New on right looks like a general purpose, off the shelf seal.

old 'un bit more "special to the job" with a built in dirt shield to help protect the actual seal part of the seal!