A quick search of the forums yielded only debate over Synthetic vs Conventional, so I will give it a go here:

The previous owner of my Jag told me he only ever put in 0W-40 Synthetic Mobile 1 European Blend. I only take the car out in the summer so this grade is perfect for the temperatures I encounter.

Now I am inclined to use only what he has used, since the car does not burn or leak any oil, but I have noticed that the European blend has been discontinued and replaced with Mobile 1 European Blend FS.
https://www.christopherprice.net/mob...1-fs-3460.html

A look at my local shops confirm this as all Mobile 1 European Blend formulas have the FS designation on the label.

Is it okay to use this FS blend in the Jag?

 

I wouldn't be running 0W-40 in there in the first place; 0W-30 would be a much better choice for your region.


At any rate, Castrol 03101 is a direct drop-in:



The dexos2 rating is what you are looking for, in general.

 

Thank you, meets all the specs, just what I'm looking for.

0W-30 would be good for the winter according to my owners manual (-20F to 20F), but I only drive it in the summer where the averages are in the mid 70's to mid 80's. Sorry for the bloated pic!

 

I'm lining up the dates and I'm pretty sure the last oil change the previous owner did he put in Mobil 1 European Blend FS, which meets the API reqs. but not the ILSAC GF.

Looking at this spec chart on the Mobil 1 FS 0w40: https://mobiloil.com/~/media/amer/us...pecs-guide.pdf
I see the zinc and phosphorus levels are significantly higher than the stuff that meets the manual's specifications for my car.

I wonder if this will have any adverse effects. It doesn't seem to have any performance wise anyways. I am going to go with the Castrol in the link you provided.

 

This is overly complicated...Jaguar specifies 5w30 for the X-Type, Castrol being their preferred brand. But having had 3 of these cars I can tell you that any premium 5w30 works perfectly, and no, you don't need to use a full synthetic.
For the record, I have always used Castrol GTX 5w30, not a single problem with the X-Type engines, ever. And that is the grade that I use all year round here in Victoria where winter temps rarely go as low as freezing, but summer temperatures can be in the high 20's and low 30's C.
The current engine range in Jaguar's is a different thing entirely

 

Wal mart Mobil 1 costs as much as conventional which I wouldn't use with the tolerances of these engines.

 

I recently changed the oil in my '06 3.0 for the first time since taking ownership. I have used Mobil1 full synthetic in previous Jaguars with no issue at all and this one takes the 5w30.
Difference? Revs at 70mph are almost 200 less!