hi,going to do an oil service on my jaguar xj6 x300 1996 can anyone advise me on the correct oil,its done 123ooo miles,been told 5/30, and also 10/40 ???

 

I use 10W/40, always have in that car.

I find the engine quite sweet on that brew.

Others use different viscosity.

 

I use 10/40 as well

Cheers
DD

 

Here is a quick guide I made:

jaghelp.com: XJ6 Fluids and Filters reference guide

 

thanks guys,10/40 it is

 

5/40 Rotella T6 Syn here, after trying 10/30 and 20/50.

 

The Owner Handbook normally tells you what oil grade to use, but for a car of that era, and in the absence of the book, I would agree with Doug, use 10W/40. There is also a 15W/40 too, that you could use, especially with those miles.

 

Try, or check-ask for Lubrication Engineers oils-lubricants.
You will be surprised, if try them, on their products.
This is not an advertisement, I use them all around, cars, motorbike, factory.
7 years in a car, 12 years in the motorcycle, the same oil just filter change and fill up.
In the factory I work, 600HP centrifugal compressors running round the clock, 1081 rps, yes revolutions per second, not rpm, the impellers shafts (plain bearings), 9 years the same oil, the viscosity is up to you.