The rubber edge of the duct came off a while back, Do you replace the vent and how useful is it? I assume Jaguar didn't put it there for looks. This is the vent that sits behind the oil plug.

 

This black rubber piece is designed to funnel cooling air over the transfer case. It most often goes missing when the engine oil is changed by Jack-the-bolt thread-stripper as he over-tightens the drain bolt - he sees no use for it so he fails to put it back on. But sometimes it is torn off also by road debris or road snow. The duct must be removed to access the oil pan drain bolt. And you are correct: Jaguar is not in the habit of putting unnecessary parts on its cars - it is a necessary piece and it is held in place by a peg and a bolt so it is very easily replaced. The part number is C2S18834 and the bolt is C2S2665. If your car does not have this duct in place you should replace it. How can you tell if it is installed? it is easily visible as the lowest part of the engine assembly:

 

Mr rx-7 tt: does this (#2 above) answer your question?

 

Part no longer available according to the local dealer.

 

You can do a search in this forum for a step by step guide of a member quite awhile ago who fabricated a metal (aluminum?) one for his car. He got tired of them tearing off in the snow. He has pics and template measurements as I recall.

 

Thanks for your replies, I’ll figure out something.