Hi I'm new to forum, So would like to say "Hi" to everyone, I have a 2013 Autobiography 4.4sdV8 in Barolo Black, I keep loosing coolant from the expansion tank, there are no signs of a otherwise leak and car doesn't over heat, Does anybody have any ideas or suggestions?..

Are you over filling it ?

How much are you losing ?

What drew your attention to it ? Not somrthing I regularly check......

These expansion tanks have a known fault of developing a fine hair crack in one of the corners which allows a fine mist to escape which dries in the heat of the engine bay. Try replacing for a new tank.

Otherwise it may be your camcover gaskets being old and drying up.?

Warning light comes up on dash, loosing entire tank, but it seems to be intermittent... filled it to correct level and it was fine and has been for over a week, light came on this morning,tank was empty but system seemed full, topped it up had to go to heathrow, when i got back it was empty but temp gauge was normal..!

Hi Dolphinboy, the car is only 4yrs old!. (L405) so its a new shape,

In my experiece, you need to lose quite a bit of coolant before it's likely to overheat

A slow leak is a to find - as Dolphinboy says, it can quickly evaporate.

I hadn't realised the L05 had a coolant level warning light - that's good to know