Trying to find information on what this is. I found it pictured in the manual but never referred to. It’s currently leaking oil and I want to fix that while I’m in doing timing chains and tensioners.

 

Almost 7 years ago, a user made a single post in a related thread about the same thing leaking. That was the only post made by that user, and no definitive solution was posted (as this question relates to the 5.0 engine, and the thread was about a 4.2 engine oil leak).
See post #12 in this thread:
Aw Crap, Oil Leak

 

It's the cover for the high pressure fuel pumps auxiliary drive shaft sprocket.
Get a copy of the AJ133 Technical Training pdf from my Dropbox here:
https://www.dropbox.com/scl/fi/s21me...=x4cqiit5&dl=0
This shows the fuel pumps drive shaft, sprocket and chain set-up but doesn't show the sprocket cover in any detail.

 

It is a vacuum pump for brake servo.
The pipe from it T's into the manifold vacuum line.
It is fitted on the end of the fuel pump shaft.
​​​​​​Fairly easy to replace it's seals now you know what it's called😁

 

The seals are not available separately from JLR. Here is a link to a company that sells a 'kit' to reseal the vacuum pump. Note there are two different versions of the pump.

https://www.rkxtech.com/collections/...nd-rover-pumps

 

Note to remove the vacuum pump, the lower cover under the engine must be removed, and the engine oil drained prior to removing the pump from the front of the engine.

To remove the cover, drain the engine oil, and clean and overhaul the pump requires about one hour of labour.