Hi! I am living in a cold part of Norway where we easily gets -10 and sometimes -20. Bot this November/December has been warm. I recently bought a 2.4 litre automatic 2002 model Grand Voyager with 122.000km. That's about 57k to 80k miles. When I start the engine it sounds pretty smooth, but after some minutes a soft/not so strong ratling comes from the engine. For all I know it can be a lot of strange things like the AC, but it is off all the time. I was thinking about rod or crankshaft bearings or hydraulic valves. I think that the engine now have some Castrol 5W/30, but I am not sure. Should I try to go up or down on viscosity? They have pretty wide range of oil where I buy for reasonable price, so I am open for other oils than the ones in the headline.