Having just purchased a 2005 XK8, regularly maintained and serviced by a Florida Jaguar dealer, it seems to me that the previous owner may have been changing oil more frequently than needed, and I would like some opinions from members. The car was having its synthetic oil changed every year, with only 1 to 2 thousand miles annually. Given the typical warmth of Florida, and now in its new home in Georgia, and given the lack of condensation that would be experienced farther north, is it really necessary to change oil - synthetic, at that - every year? If it's thought that oil should be changed regardless of appearance or odor, is synthetic oil necessary in the first place, and is there any problem using semi or non synthetic oil, and changing oil on a mileage basis? Thanks!

 

You will get a lot of opinions on this. In your situation, I would change it once a year if you are driving it 10K miles or less each year regardless of which oil you are using.

 

At those miles, I'd still do it twice a year, end of summer and beginning of spring.

 

Opinions are one thing, facts are another.

None of your choices in the poll is accurate.

If you consult your owners manual, there is no requirement to use synthetic oil at all. During the 'free maintenance' period when the car was new, the servicing dealer used non-synthetic as that's what Jag specified and payed for.

There is no evidence that suggests there's any advantage to using synthetic oil in your generation or previous generations of Jaguars.

The factory interval for non-synth oil is 10K miles or annually. More often under average driving conditions is pure waste. Using synth. oil at the same intervals is also pure waste.

It makes many people feel better by feeding their car exotic and expensive boutique oils. That's OK, but the car couldn't care less.

 

+1

A few years ago some of the forum members spent a lot of time and a few dollars discussing oil testing which is the way commercial fleets schedule oil changes. The feedback from the testing laboratory was that full synthetic oil only reached it maximum lubricating qualities at about 13k miles. Full synthetic did not drop below technical specifications of the SAE rating until about 18k miles. Your mileage may vary.

Other than the condensation issue in which an engine that is run up to operating temperature on a fairly regular basis will not be an issue the life of oil in an enclosed engine is effectively years, many years.

. . . and I said I would never reply to another oil thread . . . .

 

With modern oils the main reason to change is to change the filter and to eliminate metalics and contaminates in the oil. In that respect I don't see a difference between synthetic and conventional.

 

then why do my cars I run regular oil in look dirtier then my cars I run Mobile 1 in at the same mileage from an oil change?

 

Colour of the oil is meaningless when it comes to condition.

 

The oil in a whole house generator using propane as a fuel is perfectly . . . . perfectly . . . clear at the specified change interval. Makes you wonder if you need to change it.

 

color of oil makes no diff??? so after 3500 miles in my 135k mile honda the oil is much darker and easier to read on the dip stick (harder to see when fresh) means nothing?

 

More indication that colour is not a good reference.

 

The only tidbit I have to offer is this: I used to follow the recommendation of changing the oil annually or at 10k miles, and now I have permanent VVT clatter at startup, which is believed to be caused by infrequent oil changes. I now change my oil at much shorter intervals. Take from that what you will.

 

I've put 90k miles on her in less than 4 years. For no scientific reason at all, I change the oil around 8K miles with the most affordable synthetic I can find and a NAPA Gold filter. It seems to work. But like I said, there's no justification for this. However, If my car sat, doing nothing, for as long as yours, I might consider using the cheapest regular oil I could find and changing it twice a year. You really need to drive (and enjoy) that car more than 2k a year. I put more than that on my '68 Triumph GT6 Resto-mod Show Car.

 

I change at 6500 miles, and when it comes out, it is definitely
time for a change.

Now, the second to last oil change took two years to get to
6500 miles. In my mind, not a problem. The sump is fairly
well sealed, an oil jug is fairly well sealed. If you would leave
an oil jug for two years and still use it, what's the difference?

Testing whether the oil is okay to continue from 7K to 10K is
an exercise in onanism. The money used for the test may as
well just be used to purchase nice new oil.

I have used both conventional and synthetic depending on
my whims about viscosity.

There are certain physical advantages to synthetics.

The one thing you should be aware of is that in the ROW
oil specification that is not hindered by CAFE/EPA or by
non-availability at the time of printing, the specification
is ACEA A3.

It is now readily available and probably the best spec to
use. It is simply a superior spec to API/ILSAC.

You will find that almost all ACEA A3 oils are synthetic. It's
tough to meet the spec with a conventional oil

However, my latest round of reading suggests that
I will be going back to Shell Rotella in either 15W40 conventional,
or 0W40 T6 synthetic. This is because HDEO(heavy duty engine oil),
normally exceed even the ACEA A3/B4 in the critical specification of
HTHS.

Currently on Castrol European 0W40 meeting ACEA A3/B4.

To find it, the bottle must say "Made in Belgium" on the back.

 

The darkness is contaminants held in suspension ...
or permanently sheared viscosity improvers.

If the latter, that is bad news. The oil is done.

 

After reading this thread, I am going back to a 10K vs 5K interval. I do use synthetic because it is almost as cheap as conventional at Wal Mart. Changing the oil is a hassle given the front drain plug, so doing it half as often will be great.

 

I have always used regular oil per each car manufacturer's recommendations, including in the XK8 and change it at 5000 miles. The Jag goes 2 years between oil changes with 10W30 oil. My pickup uses 8 quarts of Mobil synthetic 0w20 so I guess I have to get used to $60 oil changes. The truck tells me when to change it, via email. In contrast, my garden tractors get new oil and filters every 50 hours or so. I have some 30 year old 10w30 oil in pasteboard quarts that are no doubt still good. I feel its the miles, not the months that are important. The point is I'm very casual about oil changes but I constantly check oil levels and have never had any oil related issues, ever, in 50 years. I hope I didn't jinx myself! PS I just changed the oil in my father-in-law's 27 year old Ariens with a 5 horse Tecumseh. It was slightly over-filled when I got it and was blowing oil out the vent. It had only been changed once in it's entire life and has been sitting in his shed for 20 years. It runs like new after cleaning the carb.

Stop obsessing over oil. Same goes for transmissions. I have never changed or even added transmission fluid to any of my cars in 50 years and they all go at least 100,000 miles.

 

This is an interesting thread...with some of the usual "hip-shooting" on the key issues. Color of oil means nothing? I always believed that oil color indicated a level of contaminants in the oil...contaminants that detract from the oil's role of reducing friction. As far as following the manufacturers suggested intervals...in my case, the "book" was written 18 years ago and the technology of synthetic lubricants have made those intervals and other fluid change issues irrelevent. Finally, considering the history of these cars as documented in innumerable examples in this forum clearly indicates that 5k or one a year minimum changes in oil and coolant are necessary preventive maintenance tools in keeping these vehicles healthy.

 

Wow, talk about 'shooting from the hip'.

Can you point us to any actual examples?

The sheer number of owners who used the factory recommended type of oil and viscosity and followed the recommended interval without issue clearly points away from Jag having gotten it wrong.

 

As stated the poll questions would be misleading if any were checked.

Regardless of what others feel as to each there own idea and science facts are varying on this discussion.

So I choice to reject everyone else's reality and substitute my own...

I use full syn oil and change yearly on a XK8 with, as of today, 98K miles. Car is driven less than 5K a year. Just makes me feel good to do it knowing that it is getting the best care I can offer.