My 03 Disco makes a loud gurgling noise when making a turn whilst going uphill. I'd like to know what it is and whether it is damaging. It also leaks rain through the headlining and even comes in through the sunroof controls. Garage I got it off took the sunroof apart and changed the seals
etc which seemed to cure it but its happened again

 

The gurgle when you turn and go up hill and put more load on the engine is very likely air bubbles in the coolant lines that circulate thru the heater core. Coolant is always going thru there, even when AC is on. Try bleeding out the air of cooling system. If it keeps coming back, could be a sign of head gasket leak. Keep eagle eye on coolant temp. If head gasket, those bubbles will be exhaust gas, and there is a $50 chemical test for that.