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I have a 98 XK8, what are peoples preferences for engine oil and what do you consider the best make for the 4.0 V8?
Dave

I`ve just done this job ten minutes ago! Christmas service on my S-type V8 which has basically the same engine as the XK8.

I favour fully synthetic oil which does not burn in use un like semi synthetic which always comes out black after 6k miles. Synthetic comes out much cleaner. I`ve also found oil consumption to be less using fully synthetic.

I use Comma X-tech 5W 30 which is recommended for the 4 litre V8. My factor will sell me a filter and 2 x 5litre tubs of oil for £53 inc VAT. Seems a reasonable price.

This latest oil change used a Coopers Fram FT5722/Z1240 filter and a new Jaguar supplied sump screw complete with new O-ring seal under part number JZH100062. If you have a box of metric O-rings handy, you can avoid changing the sump screw. Just replace the O-ring.

Mike K

personal preference is key ,

but there is no need for the more expensive fully synthetic oil , and if you read about oil its not 100% synthetic anyway , its varies up to a maximum 30% of volume, the rest is ordinary mineral oil and detergents etc ,,

so a good quality semi-synthetic is the way to go as it is what is recommended and is cheaper , on an older higher mileage engine i would go for a 5W30 , or even a 10W30 , and i also put in an additive to mine , as it reduced startup wear and any smoke on startup , well, she is 13 years old and 110k miles...........


the most important thing is regular oil changes , mine gets one very 3k miles or 6 months , and a new filter every other change , talking about filters , they are a tenner from Jaguar with your JEC discount, and thats cheaper than the high street !!!! and its a genuine Jaguar branded filter to boot, so looks good under the engine as well....

just my thoughts, and you will get a different view from most peeps who do their own maintenance

BB

My article, written in conjunction with Mike Horlor, "The problem with oil" in the Nov 2009 edition of our magazine explains more.

Synthetic mixes are designed to combat the shortcomings of more basic mineral based lubricants. I`ve always run Jaguar V6`s and V8`s on synthetic oils until my oil change last year. In an economy drive, I refilled with a semi mix. A couple of months on, the oil began to change colour. (Yes, I know it should as carbon and combustion by-products together with hot working temperatures lead to this effect) Previously on fully synthetic, the oil would remain golden brown to the end and not drain off a black colour as indeed occurred this morning.

Today having drained that semi oil, burn and contamination was noted. That has never been the case when I`ve used a fully synthetic oil. These oils often exceed original specification lubricants. As far as I`m concerned, they may not be 100% synthetic but more design technology will have been included when compared against a now common semi oil.

Fully synthetic oils are vastly more resistant to burning than predominantly mineral based products which have a tenancy to sludge towards the end of their working life. One of the reasons why synthetic oils were produced. Mixed semi synthetics go some way to combating some of the problems associated with predominantly mineral based lubricants.

I used to use additives in engine oil. No longer, I`m afraid. It is well known that some after market products frequently cause more problems than they solve as they can be incompatible with a particular motor oil. Many claim reduced start up wear. I wonder how that is measured ?

Another reason I prefer synthetic oil is that it is claimed to be better at handling cold start fuel dilution and offers better wear resistance to a semi synthetic oil. If a semi synthetic oil is adequate for the job, it should not be necessary to add an additive at a cost which probably equals buying a fully synthetic oil in the first place...........If it is indeed needed, why not just buy synthetic and avoid the risk of additive incompatibility?

In the same way that it is well known that mixing WD40 and grease together will often lead to sludge formation, I am now loath to mix combination lubricants in an engine in a similar fashion.

Mike

pays ur money , takes ur choice......


BB

I asked the garage what oil they used & use same

Allan