Jaguar X-Type JJM 21 02 20/15 - Manual (Page 157)

Maintenance 7-7
Recommended engine oil
When the oil level is at the lower dipstick mark, add 1.0 litres of oil:
Oil specification – API SJ / EC and ACEA A1-98 or A3-98.
SAE Viscosity Rating
Recommended SAE Viscosity Range / Ambient Temperature Scale