How much tire pressure are you running? The vehicle manufacturer's reccommendations are for a vehicle running at the rated gross vehicle weight (ie full load). Weigh your truck with what you actually carry in it, and look up the load/inflation tables for your size (either in the Tire and Rim Association Yearbook or online where they can be found with some searching) and air down accordingly.

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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 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.