coolant liquid
 

hi all,any help with my 2001 4.4i (158000km) loosing coolant fluid. it dosent leak , but seems to be topped up with 500ml every 500km. the warning message "check coolant level" comes up on the dsiplay to prompt me. cars runs well with no overheating problems. any ideas?2 years ago i changed the radiator and hoses due to a cracked radiator.is it time to trade-in?thanks

It could the water pump or more likely the valley pan. You can't see the valley pan because its beneath the intake. If you cant see a visable leak or white crust residue due to a leak it very well might be the valley pan.