How can I fix an oil leak from the drive shaft of a 2007 Renault Master va?

when you say driveshaft oil grooves,do you mean the splines for locating into your diff?you should have a machined, flat,smooth face which should sit on your diff. oil seal and don`t understand why the garage would not see that it was situated wrongly and still leaking,not sure on your model but were there circlips present on the diff.end of the driveshaft to locate them into the diff?can you hear them click into place when fitted?would maybe take it back to the garage and point out what you are experiencing and ask them why they put a job out which was not complete.

cdc
March 2012