The oil looked like that at 30,000 miles? Ahhh... I will change my soon since it has 48,000 miles. I had the rear end whine on my 1997 XJ6 (just sold the car yesterday). I happened at around 55,000 miles. Luckily, I was able to purchased an entire rear end (sub-frame, shocks, sensors, brakes,and all for $300.00). My friend and I dropped the entire rear end and swapped. That was five years ago.

Thank you for posting those pictures! So just one bottle (1 quart) to refill with fresh gear oil? Need to do mine asap--been 82k miles and never serviced...

The capacity of the diff is 1.3litres which is over 1 quart. I was surprised I managed to get 1.3 liters out with my pump. You will need 2 quarts to get the volume in the bottle to squeeze the oil into the diff. The accesses is problematic, and the bottle is below the height of the diff. It would make life easier if you had an extension tube for the gear oil bottle. (avail at auto zone type places for a couple of $)

brakeboost,

I have one of those gear oil bottle extension tubes, and it comes in handy on our XJ40 because I can access the diff fill hole through the trunk bulkhead. For the X350 it might be easier to use one of those cheap orange fluid transfer pumps like the one shown in your third photo. I used one to refill the diff and transmission on our BMW and it works really well. With small 1 quart bottles that can easily tip, I prop the bottle between a couple of heavy items like a toolbox and the jack so I can use both hands on the pump.

The pumps are inexpensive enough that I keep a few of them on hand: one for removing old fluids, and one each for refilling with clean ATF and gear oil. I just labeled the pumps with a Sharpie permanent marker so I don't use the "old oil" pump to install new fluid, or the ATF pump to install gear oil.

Cheers,

Don

Are those the correct placings for axle stands at the rear as shown in your last picture?
Do you use a jack to lift the rear of the vehicle ad if so where do you place that, under the diff?

The take away here is obviously that differential life can be extended greatly by a fluid exchange at reasonable intervals. Not sure what those intervals would be but with 109k miles on my 06 XJ8L you can bet I'll be using some type of fluid pump/siphon to pull what I can out of there and doing perhaps 2 changes close together with perhaps 500-1000 miles in between the 2 changes.

Cambo351: I always appreciate the technical details you provide. Seems you always have stuff that I don't see anywhere else, so thanks. Do you know at what date or serial # Jaguar went from Gen 1 to Geb 2 on the differential on X350 cars?

Mt X308 had such a loud rear on it that I sold it out of fear of an expensive repair. It had an obnoxious whine even after a full fluid exchange to Mobil 1 Synthetic gear oil. In my current car the plan is to change the oil BEFORE it starts sounding the death nell.

Good idea with the multiple use of those inexpensive pumps; I think I will do the same. The problem, as I am sure we are all familiar with, is keeping the cheap plastic tubes where they were pointed, especially in cold weather. I'll try some small spring clamps from my woodworking next time.

Thanks

The correct floor jacking and support points are in the workshop manual General Information P81(there's also a warning about asymmetric lifting). I would never lift a multi-link suspension vehicle by the diff. I think I remember reading that last years Mustang was the last American car with a rigid rear axle. Whilst I used to 'lift by the diff' in the 70s (UK), the cars where a lot lighter, and there wasn't much to break on a "Dagenham Dustbin."

Ah, that makes sense now. Thanks for clarification.

A funnel works well for this job.

Put a long piece of vinyl hose on the funnel outlet, put other end of hose in filler
hole, hang funnel on a magnetic hook located high up on the right rear quarter
panel. The hose should be draped down into the wheelwell and to the filler as
directly as possible.

Pour in diff lube until it drips.

my old dad used a red Wesco oil can. I still have it, but also a modern version which has the translucent plastic hose, which is handy if you have one for filling gear oil and one for red steering fluid/atf

Wanted to post a follow-up since I did my diff oil today. My surprise was that my gear oil really did not need to be changed at 83k miles. There was next to nothing on the magnet, and the oil was still gold colored, only slightly dark, and smelled like gear oil should. Nothing burnt. The photo was really difficult to capture, but you can see it's still translucent and gold. Got out just 1 L, and replaced with Mobile 1 75w140 synthetic.

Did it need new diff oil at this mileage? In my opinion, no. Will it hurt to have changed it? No, certainly not.

https://cimg9.ibsrv.net/gimg/www.jag...4db4544878.jpg

Sorry, missed this before.

The Gen1 diff was only ever used on the S-Type. The X350 started out with Gen2 and then went to Gen3 at the end of the production run.

Have a look here https://www.jaguarforums.com/forum/j...ntials-134733/

that's very clean. My magnetic plug was quite fluffy at 65K miles.


Do you think it might have been changed before?

Who can find it? Cambo Can!
 

Thank you sir. No worries - it was not critical info but more a case of furthering my X350 knowledge. When it comes to technical data, I have seen you post details on things that I have seen nowhere else. I thought I was really good at finding info on the web, but when it comes to research, I bow to your greatness! :icon_worthy:

No, I can almost guarantee it was not changed before. Car was still under warranty when I bought it and all service was done at the dealer (even oil changes).

And this car has seen mostly highway driving--the previous owner did lots of runs between NC and FL, so I was expecting to see it quite burnt. The power steering fluid was much worse at 50k miles. This diff had little more than break-in debris in it. No matter, now all of my fluids are up to date.