What tool/method are we using to get the rear diff plug out?.
Not much room back there either.. Grrrr

 

Pretty sure it's on the back face, (facing rear of the car), about half way up the differential case/body. I think it's a 3/8" square socket wrench that fits into the drain plug. Righty tighty, lefty lucy

What type of gear oil are you putting in?

 

The only thing i could get in there was a 3/8 ratchet which had the square face cut down (i use this ratchet to fit into the narrow area of the transfer case)
That seemed pretty loose to me, when i tried turning, the ratchet spun in the 3/8 square hole,
Didn't try again, sprayed with penetrating oil then got on with the day

 

Just did this over the weekend and it's a 3/8th drive. Used the grinded down ratchet trick. To empty and fill I used a small 12V pump.

 

I recently changed the oils in the transfer case and the 5 speed transmission, April 2016. Below is an excerpt from a post of mine in 2010, just after I bought this Jag with 80k miles on it. I was getting dirty going thru the gear boxes as I was instructed to do on the Jaguar Forums for best results.

"I did my rear diff. & my TC this past weekend. On the rear diff. I used a hand siphon pump and pulled out a little over a liter of black gear oil, my car has 85,000 miles on it. I then pumped in the same amount of RedLine 75/140 synthetic gear oil.

Unlike the TC, the plug on the rear diff. is high enough that just as I pumped in a little over a liter of new oil, I started to get a few drips coming back out, but I was done so I just replaced the magnetic plug and voila."

I have done it once since then, but it's probably time right about this weekend. The same gear oil is in the TC and when I did that one a few wks ago, it stunk like petroleum *** in a bag of ****. freaking awful.

I like the idea, but I don't have an electric pump. I use a hand squeeze sphon pump. Old sKool

 

I managed to acquire some square rod which I filed down to fit and cut to length. I then used a spanner on the rod to loosen the plug.
(this was on my previous X Type 2.5L)