I think ZF recommend gearbox oil change around 70K but please check.
I’ve had 2 Megaflush now. One at 83K when I purchased in 2018 and second at 120K in 2023.
No issues before or after. Preventative maintenance is key
Bodsy did both. www.updatesbybodsy.co.uk Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
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I also used Bodsy for the flush and have had no issues at all. Had mine done as recommended by JLR at 10yr service