2013 Volvo B60 T4 is using a lot of coolant

The cooling system on a modern engine like the one in your Volvo should be a sealed system, capable of catching and recycling any overflow from the radiator. It does this by using a catch tank or expansion tank which allows a small amount of coolant to leave the radiator when the engine is hot, which is then sucked back in to the radiator as the car cools down.

As such, there shouldn’t be any need to top up the coolant on a regular basis. You might lose a tiny amount from evaporation over time (or possibly not) but if you’re topping it up regularly, then you either have a leak or an engine problem. Common engine problems that would cause coolant loss include a blown head gasket or a leaking water pump. A failed transmission cooler could also allow coolant to escape, probably into the gearbox where it would destroy the transmission, so you’d likely know about that by now.

But the first thing to check for is a physical leak somewhere in any of the plumbing, the radiator or the expansion tank. Modern cars often have a lot of cooling joints and junctions, many of them are made from plastic and all of them are potential leak points. Also, take a big sniff of the car’s interior. Does it smell musty or damp? Are the carpets in the front damp? If so, you could have a failed heater core (which uses coolant from the engine to heat the cabin) that is allowing coolant to escape.

You can also park the car overnight over a large piece of cardboard and watch to see if any drops of coolant appear somewhere under the car., This will help you trace the source of the leak and will make diagnosis easier.