I have a 1996 XJS with the AJ16.

I did an oil analysis on my XJS. I've had it since about 60,000 miles and it's knocking on the 90,000 mile door now. I've been using Mobil 1 synthetic ever since I brought it home and have done so for the extended change interval. I've been running about 7,500 miles between changes. This one went a little longer at 7,743 miles.

The analysis isn't great. They've asked me to provide another sample at 4,000 miles, which I plan on doing. I'm attaching the report here in case anyone else has some input.

Apparently Mobil1 0w40 European Formula is not going to save me on any oil change interval based on this report. I've used the 15w50 and the non-Euro 0w40 formula in the past as well, not sure it has any bearing on these results.

I'll provide the followup to this in 4,000 miles, in the meantime, enjoy.

 

Vee,

Interesting reading. I'm slightly surprised at the comment that increased wear is seen after 4,000 miles. I thought modern semi- or full synthetic oils were good for 12,000+ miles. I do change mine every 6,000 or 18 months but might rethink that now.

I think I might try and find a place that can do this type f analysis close to me and send mine off for assessment. As a matter of interest how much oil did they need from you and how much did they charge for the report?

Cheers

Paul

 

I sent it to Blackstone Labs. It's $28 for the analysis and an extra $10 for the TBN report which Do I Need a TBN? can explain to you what it is, why I paid the extra $10, and why I won't need to next time.

 

I'd be very reluctant to draw any black/white conclusions based on just one sample.

 

Mikey, I agree with you.

I'm definitely providing a follow up sample at 4,000 miles just to see what happens. As mentioned previously, I'll share the results with you as well on this thread.

Increased metal could be from the timing chain chatter I get at startup sometimes.

 

Great info. I'm about to change the oil for the first time and was wondering what to buy. I think I'll just use non synthetic.

 

Al,

I would politely suggest that you definitely shouldn't use anything less than the original Jaguar recommendation which is a semi-synthetic.

Paul

 

?? You sure? Jag made no recommendation of using semi-synthetic oil in this engine. The supplemental bulletin requires full synthetic but only if either 0W30 or 5W30

 

Not so fast.

My TBN is still high, so theoretically the oil did fine by the 7,500 mile interval. The next result will find out if the interval will pull the iron numbers, etc back into an acceptable range.

Assuming that's the case, I might switch to a regular oil, but since I'm buying 5 quart jugs from Amazon and/or Walmart for less than $25, is there really a cheaper alternative?

I guess there are alternatives down to the $20, maybe even $17 a jug.

 

Mikey,

I didn't mean the handbook, I just meant the original Jaguar Service Division at Browns Lane (originally). I suspect they've moved to full synthetic now, although I still use semi- because I tend to change it quite often so believe (perhaps wrongly!) that it's fine for my use.

Paul

 

Do you have something more recent than this TSB for recommended oil for an AJ16?


http://www.jagrepair.com/images/TSB/XJS/12-58.pdf

 

Is this fact or just lore passed down? Why would Jag factory-fill with semi-synthetic and not recommend/require dealers and owners to do the same?

My dealer used non-synthetic on all cars, at least while my car was under warranty until 2006.

 

I would totally agree with this. I did the oil analysis when I was in the trucking business - every other oil change - of which my intervals were about 10,000mi / once monthly. Granted it was a long time ago, and different engine, usage, etc, but as it was explained to me back then, the utility was more for seeing trends, or sudden changes, than as a instant condition check. For example if certain values spiked it could indicate a bearing starting to fail. For the trucking business it would have been way cheaper and easier to repair almost anything at home rather than out on the road somewhere.

Eric

 

Exactly. My background is commercial aviation gas turbine engines but the principles are the same.

A single oil sample is almost meaningless as no two engines follow the same pattern and an individualsample may indicate false positives as easily as it might miss something important.

A baseline must be established through several samples followed by regular tests to be of any use.

Kinda like a doctor taking one blood sample of a patient at age 50 and making critical decisions based on that.

 

Yes.

Use the money spent on Blackstone to buy oil and change it a bit more often.

 

That's an interesting TSB reading between the lines.

On the NA AJ16, 0W30 and 5w30 are allowed above 10*C if and only if
the oil is full synthetic. On the SC AJ16 and the V12, not at all above 10*C.

And the 5W20? Below -10*C only, on all variants.

Makes one go hmmm.... about thin oils.

The 5W50 seems to be approved for complete coverage in all temperatures.

Castrol makes a synthetic 5W50. I had it in for the previous oil fill.

BTW, over at the oil site everyone knows, people seem to be wandering away
from Mobil European 0W40 as being somewhat thin. The usual substitute is
Castrol European 0W40 with reports of quieter startup noises.

 

Mikey,

It's a fact that Jaguar Service Department at Browns Lane were putting 10w-40 semi-synthetic in AJ16 engines when I got my current XJS in 2002. I knew the guys in the department then, but I'm not sure what the current department use. The 3 Jaguar Dealers closest to where I lived in 2002 all used 10w-40 semi-synthetic for AJ16 engines.

Jaguar Dealers are directed by a book that is regularly issued by Jaguar which details a whole variety of vehicle specifications including lubrication standards. I saw my dealer yesterday and he showed me the current version of the book. Unfortunately as time moves on, it now doesn't cover any vehicles before 2000MY. It only details oil spec rather than type. For example for your NAS 2003 4.2 S-Type it states API-SL & ILSAC GF-3. It's apparently up to the individual dealer to then determine which viscosity and engine type. I asked my dealer what they would use on the S-Type and on my AJ16 XJS. He said they use Shell Helix 5w-30 full synthetic in the S-Type and 10w-40 semi-synthetic in the AJ16 (unless the customer specifically requested or provided a certain oil). They said they use Shell Helix full synthetic in all post-2000MY cars. So it seems Dealers have some latitude as long as the oil meets the defined spec.

Apart from the cost, I'm not aware of any downside to using semi-synthetic rather than a mineral oil in an AJ16. Oil is cheap compared to everything else that I might spend on the car!


Vee,

I apologise if this has gone slightly off-track from your original post!


Cheers

Paul

 

Not at all, Paul! I find your piece of the discussion relevant and interesting. Thanks for posting!

As for spending the money on more oil changes, instead of Blackstone, you are probably right about that Plums, I'm going to do it one more time, after the recommended 4,000 mile mark, just to see what happens.

I used to use 15w50 for my spring oil change and back to the 0w40 for the fall change, I may reconsider that, or hell with it, if I'm going back to 3,000 mile interval oil changes, I'll stick with the cheaper stuff altogether and ditch synthetic.

 

The above has been thrashed many times. The oils and the specs that a Jag dealer might use now in many cases did not exist when the cars were built. There is no documentation indicating that the revised specs are retroactive. There is no requirement in the S-type owners manual to use semi- or full synthetic oil. Is there one in the XJS manual?

S-types sold in North America were serviced with non-synthetic oil by Jag dealers if the oil change was part of the free maintenance plan. Jag HQ would not pay the extra for anything else.

 

I decided to change from Mobil 1 0W40 and try a OCI with Maxlife semi syn 10W40... No reason for the change but just decided to try something different.