Triumph Stag Engine Service Kits

Modern oils often contain additives that can be detrimental to classic engines. These engines were designed for oils with different chemical compositions. The Castrol Classic XL is specifically formulated with period-appropriate additives that protect your classic engine without risking damage to older components like brass, copper and unique alloys common in pre-1980 engines.

The 20W-50 multigrade formulation provides excellent viscosity stability across a wide temperature range. It maintains proper oil pressure at the higher operating temperatures typical of classic engines, which is particularly important for British marques known for their cooling system quirks.

Castrol Classic XL was developed with extensive testing on British engines from the period, particularly MG, Rover and Triumph models. It accounts for specific characteristics like higher operating clearances and the metallurgy of these engines, providing optimal protection for brass and bronze components commonly found in British classics.

While modern oils might allow extended intervals, we recommend changing Castrol Classic XL every 3,000 miles or annually, whichever comes first. This conservative approach accounts for the different filtration systems and potential contaminant build-up in classic engines.

Yes. The carefully selected viscosity and additive package helps maintain better seal conditioning and reduce oil consumption - a common issue in classic engines. Many users report noticeable improvements in oil consumption after switching to this formulation.

Indeed. The high-quality mineral base oils and carefully balanced additive package make it ideal for running-in rebuilt engines. It provides the right level of protection while allowing proper bedding-in of new components.

While maintaining period-correct characteristics, Castrol Classic XL incorporates modern manufacturing standards for better consistency and protection. It provides the best of both worlds: period-appropriate properties with modern quality control.