Hi all, my SDV8 L405 is losing coolant slowly over time. In my experience the coolant system is sealed and should not lose any unless there is an internal or external leak. LR couldn't find anything and recon it is holding pressure with no leaks. Any experiences of coolant usage?

I’ve got the same on mine, Coolant level low popped up on dash on the day of lockdown last year, LRA recovered it to the only open dealer in the South East, they supposedly fixed it but were very cagey about what they did to fix it. Not used the car for about 6 weeks because of lockdown needed to go to the Post Office so checked the levels and noticed the coolant had dropped down to the min line again on the header tank. No sign of a leak under the car, topped it up and went out, came back and you can smell coolant but I can’t see a leak.

It’s booked in for the 29th March, not planning on using it in between.

Saw this;

https://www.fullfatrr.com/forum/topic55844.html

Ah the joys of finding a slow coolant leak. My 5.0SC has one for a while. Right pain in the backside. Seems to do it more when not using it. For example a long journey of five hours at high speeds it’s fine. Leave it for a few days on the driveway and it’s low. No coolant to be seen on the floor, but it is in the middle of the V. I’m getting it fixed as it’s too cold to do it myself. But even then it’s not clear where from. The labour to chase this will become more expensive then just changing the hoses 🤣

I had this on my 5.0. Tracing the source of the leak was challenging. Two new water pumps didn't cure it. Eventually traced to the oil cooler in the V - much more expensive but now fine.

Had this with my SDV8 - garage changed the EGR cooler under warranty but was still getting low coolant issue. Took several tests and garage return visits before they eventually diagnosed an oil cooler leak. However it should be noted that none of the Landrover garage tests highlighted or proved a leak (including dye and pressure tests) and they kept trying to reassure that there was no issue. It was only the low coolant warning and lack of coolant in the bottle and top-ups that allowed me to keep insisting they fixed it.

In the end I allowed the Service Manager to use my car for a weekend before he was persuaded there was definitely still a leak even though he had been constantly insisting previously that if there was a genuine leak they would have found it with their tests.
Told its quite a time consuming job but was under warranty and it did resolve the issue.

Was never any sign of a leak anywhere, but strong smell of coolant all around the engine bay. Current Fleet:-
2019 Ford Mustang Bullitt
2016 RR 4.4 SDV8 Vogue SE - gone - currently shopping for a MY18 SDV8 VSE
2004 RR 4.4 V8 Autobiography LE
2000 RR 4.0 HSE
1993 LR Defender 90