In case any of you are still undecided whether to follow JLR's recommendation, note the second sentence of my recent Blackstone analysis. Yes, they confirm what you've been reading on this forum from various posters; change oil and filter every 5,000 miles.

 

I don’t see how you can come to that conclusion from the comments, or from the data.

 

Agreed, I don't read it as saying anything about the benefits of changing the oil and filter every 5,000 or so miles.
And I am one of those posters who recommends changing the oil and filter twice as often as the JLR recommended interval, at least mileage wise!
But what I do see is the OP using 5W-20 rather than the currently recommended 0W-20 (I fess up that I used to use 5W-20 as well but I recently switched to 0W-20 because ILSAC GF-6A) and his oil is high in Moly and low in Titanium whereas the recommended Castrol Edge brew is and always has been the other way around, low in Moly and high in Titanium so I really doubt he has used Castrol Edge.
I have never used Castrol and instead I have always used alternatives which are high in Moly and low in Titanium so this report helps confirm to me there is no need to use Castrol Edge.

 

5W-20 is what's called for in my owners manual. This sample is Pennzoil or Quaker State; oil in there now is Edge. There's still plenty of anti-wear additives in the sample, so I'm of the belief that the brand is less important than the interval (and a good filter).

The relevant item in the analysis IMO is the sentence, "(Of the samples we have tested), typical Jag 5.0L V-8 wear results after ~5,000 miles of oil use ...)". That's a pretty clear indication to me that the oil should be changed at this point.

 

Use correct grade (better if you can use correct spec), and change it often. Car should be fine. Anything else is just personal preference, IMO. If I didnt work at JLR, I would use probably PUP 0w20 and ACDelco filter - cheap and just as good as OEM.

 

It says that those are the typical results after 5,000 miles. They make no judgement whether those results indicated that the oil needed to be changed at that time.

However, I agree that the extended intervals should ideally be shortened. 5,000 just seems a little too often. My car did 7,500 a year so once a year was fine for me.

My personal suggestion is 7,500 or once a year, whichever comes sooner.

 

From the reading I have done, if you use the Jaguar Spec'ed oil, thta is what allows you to go out to the 15K miles (or whatever they recommend). The reason for this is that they have added enough anit-wear product or gotten things just so that the oil will survive to that time and still have the minimum required properties. Going with something that is not spec'ed, then yes, a shorter time frame is needed between oil changes. How often, that is subjective. You use a quality oil in our cars that is full synthetic, you should be just fine. Having say a turbo'ed car, then a special oil may be required, but that is becuase of the needs of the turbo, no the motor.

The only way that you can truly say that Brand X oil of this spec is good for XXK miles is to do what Balto is doing and analyze the oil. Then you simply need to determine what hte minimum requirements are. From there, you can figure out the maximum miles between oil changes. But, this also assumes you drive the same all the time. You say do a lot of idle time, the shortening the interval will be wise. You drive tons of highway miles on one change, then you can probably extend it some. I keep it the same number of miles just to keep things easy.

 

I change our oil based on time vs mileage.. anything over a year it gets changed unless it has reached 6k miles before then.

 

Our 6 year old XJ-L has just under 13,000 miles on it. The oil gets changed annually.............

 

Very good in my opinion