On my off road use Gurkha I flush my brake clutch and diff lock fluids every year as it goes through lots of deep water and mud. On my cars its every two years along with coolant flush. I hardly get any seal related issues. The front pads on my Gurkha have done 90,000 miles and still have 35% left. Same goes for my cars, both the Accord and 300TD have had pads that lasted close to 100,000 miles.

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99 Gurkha with OM616 IDI turbo

2015 Gurkha with OM616 DI turbo

2014 Rexton W with OM612 VGT