Just bought a used skoda with 61,000 miles. (auto)
Previous records show its been using mostly Castrol 10w40 semi.
Full service after I bought it they used 10w40 Quantum semi.
Motul suggest using a synthetic X-cess 5w40.
I am a bit wary about changing from semi to synth. Not usually a good idea.
Should I stick with the semi or can change to the synth? Price is not an issue. Just want what is best for the engine.