The car? 2006 4.2 S with 91,407 miles at the time of this analysis. I'm the original owner and the vehicle has spent all of its life on the West coast where the livin is easy and the temps mild. So, keep this in mind.
Your results may vary if you live in International Falls, Minnesota (The
Icebox of the nation)

I have changed oil and filter at an average of 4,700 miles and the air
filter approximately every 12,000. I would estimate that 80 to 85% of
my driving is highway, and, for the most part within +- of 60 mph.
That equates to about 1700 RPM for most of my driving.

In my opinion, the results couldn't be better. The company that I use
compares my engine to previous results, the results of all other 4.2 Jag
engines, and then all engines in general.

The company indicated, "Iron and all other metals read very close of averages (which are based on a 5,900 mile oil change) for this engine.
You could easily go back to 6,000-8000 miles on the oil if you wanted.
Air and oil filtration (see silicon and insolubles) were good. No gas, water,
or coolant was found in the oil and its viscosity was normal for a 5W30
product. This engine is still going strong!"

If any of you want the complete report, e-mail me and I'll send it to you.

For almost 92K miles, this engine has been trouble free. I really do like
the vehicle, and, I should keep it. But I keep lusting after the XK (it's mid-life crisis time). One of the reasons I'll stick with Jag is because of the 4.2 engine. To me, an engine that shows no wear at 92K is a damn
good engine. Once again, I have no idea how this engine would perform
on the East coast with temps dipping down into the minus 20s F. That
has to take a toll on any engine. (no, I have no intention of finding out...I've paid my dues by living in Minnesota years ago).

We do have a forum member who lives in Manitoba and he appears to be
surviving. Years ago I remember doing a charter flight to Winnipeg in February; we pre-heated those damn Continental engines for 7 hours and they still wouldn't start. I think it was -43 F that morning.

Cliff

 

Awesome stuff. What company do you use? Maybe I'll ship off a bit next oil change to see what I cook up.

 

I have been using these guys since I purchased my S model in 2006. I'm sure there are others out there but I've been satisfied with their service.
You can go to www.blackstone-labs.com to get information. They provide the mailing containers at no charge; just ensure your mechanic fills to
bottle at least 3/4 full. They charge $25 for the complete service and
another $10 for what they call a TBA. The TBA tells you the total amount
of additives left in the oil based upon the brand your using; thus, if you
want to extend your oil changes and save a few dollars you can get this
additional information.

From past experience, I determined that if I changed at approximately, I still had a TBA of 5 to 6. Waiting until 8,000, brought the TBA down to
2 to 3. It appears that with extended time on the oil, the lubricating abilities remain essentially the same, but you use up your protective
additives.

Blackstone's site has examples of analysis done on various engine types
and problems that can be found when bearings/cylinder rings, etc. start
shedding metal. To me, the presence of coolant/abrasives/water in the
oil would also signify a problem.

As I mentioned in a previous post, the airlines are religious about oil
analysis; when you've got a 5 million dollar engine hanging out on that
wing you definitely want to know when things are going south.

Cliff

 

Yes, I am still surviving, barely! -45C with the wind this morning since we are in the usual 2 week or so Feb deep freeze. And yet, took the car out this morning and started right up no problem! I try to change my oil at least every 8000-10000km, some times in the winter that has strayed to more like 15000km due to the fact I would probably die if I tried to change it without access to a heated garage. That having been said, I always keep it topped up and have never had a problem. Once up to temp, always runs strong and has never given me a single problem no matter how cold. I too have to say this is a great engine. Just about 167,000km on the clock and still going strong! Definatly has me looking at another Jag for my next car.

 

Cliff328,
Great post with very valuable informantion. I now feel less guilty about pushing my oil changes out to 6K miles. Many thanks for sharing this.
Vic

 

FWIW, I used Blackstone Labs a few years ago...wait...crud! it was 2002!!! for pre-buy analysis of my Excursion engine and xmsn oil....they said "no Problems noted" and it had 25K mi on it at purchase, now at 170K sans oil-related problems. Good info. have collected several samples from various of my cars since....but actually got around to sending few of them in. Probably most-useful if you had a fleet of similar engines and routinely submitted samples, even so a one-time sample will confirm or deny a lot of stuff and give you a good day's-worth of reading and contemplation.

 

Would you mind attaching the report? I'm very curious.

 

Yikes!
Mafioso, if that was for me...it was 8 yrs ago...but more importantly, delivered via email two-computers and several isp's ago. Hopefully I printed one for the Exc file and can find/scan. I'll look around..but it may be a few days before I can post it or confirm that it is in bit-heaven.

 

mainly for the OP, but I'd like to see what the report looks like.

 

OP offered a copy via email:


"....product. This engine is still going strong!
If any of you want the complete report, e-mail me and I'll send it to you.
For almost 92K miles, this engine has been trouble free. I really do like
the vehicle, and, I should keep it....."