Hi, Volvo recommends Castrol 5w 40 for my D5 engine.

Would it be a problem if I use Shell 5w 40?

 

Check your owners manual - Volvo states the oil specs required for your car. You can feel comfortable to use any product that meets those specs.

Just about all premium brand oils will be those specs. Just look for the specs on the oil container when you shop. Shell makes a range of products (standard dino, synthetic blend, full synthetic etc) so just choose what's appropriate to your engine/year.