www.jec.org.uk

Hi All

The car is now getting ready for the driving season and it is oil change time !

Previously I have used Castrol GTX 20 40 but is this the best for my '69' 2+2 4.2, US spec,twin strombergs with 9:1 compression ??

would like to know peoples thoughts on what is best for the UK climate ?

Mr Npw,
I certainly wouldn't claim to be any sort of authority on this subject however, I used a good quality 20/50 in my Suffolk which had the 4.2 engine and it ran just fine.
I think that because the XK is such an old ( but great ) design, 20/50 is a very suitable oil and was probably the oil of choice back in the 60's for nearly all cars although my father ran his Mk 2 using a graphite 20/40.
Good luck for the forthcoming season,

Reg

Yes, I've used 20/50 since the dark ages

The common view is a good quality 20/50 multi grade, see also the same question in the engine sections of the E board and XJ6 board