We also call that situation "brake fade". I wouldn't call a fluid change essential just because you got a bit of brake fade, but it certainly wouldn't hurt. It would also be a great idea if it hasn't been changed in the last year or two.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 401,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 26,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
99 Mazda Miata 183,xxx miles.