Warning Around Jimny JB74 Transfer Box Chain Replacement

There's an old engineering maxim that "for a seal to seal, it has to leak".  What this means is that there has to be some lubrication of the seal lip, or it quickly burns/gets torn and creates clearance and a real leak.  Single lip seals are always a bit of a compromise in this respect.

Actually if the axle is too polished there is no way for the new seal to Micro grind the tip of the lip to the surface and less likely a good lubrication. there could also be Micro grooves in a spiral form in the correct pattern depending on the direction of rotation, to transport oil on the lip surface, back in to the inside of the seal.
But now it is getting nerdy

Hi mine has just been in for the second time …leaking after I had the chain upgrade ….3 days in the dealer and ….still leaking ….now booked in for January 2025 for the next go ….thinking of ask for a new transfer box under warranty…car is sept 2022 and covered 12k miles

The transfer box is fine, it is your dealer that needs replacement..!

Yours is not a difficult repair, but dealer shop personnel and conditions often require rework for anything beyond simple parts swapping.

Fixing a leak is trivial but it takes meticulous and tedious cleaning and checking -- which becomes less likely the more times the service manager comes around to tell the tech to quit faffing on that Jimny since there are seven other cars waiting for oil changes. Charge two hours for a 10 minute oil change, or spend two hours doing a job you can't bill for?

In a private shop, the master knows that he has to make the customer happy, or he won't be in business long.  In a dealer shop, the manager knows that the customer has to be just happy enough, because hey they have plenty of other customers queuing up with their in-warranty simple maintenance jobs.  And the tech knows that he needs to keep his manager happy.

The big "gotcha" with a warranty is the requirement that the dealer network do the work. That catch really starts to bite when a dealer tech doesn't have the time or the experience -- or take the care -- to treat the machine as his own.  We're all stuck with the system, but it isn't a good one.

Anyway, fingers crossed that this time they'll bother to fix yours properly.  (It does happen, just not as often as it should!)