The 1987 GMC Jimmy was one of the last of the square-body trucks before the redesign in 1992, making it a favorite among collectors and off-roaders. If yours is feeling sluggish, start with a full tune-up—plugs, wires, and a fresh fuel filter can work wonders. And if your weatherstripping is letting in road noise, fresh seals around the doors and windows will make your ride quieter and more comfortable. One thing to check? Rust around the rocker panels and wheel wells. These trucks were built tough, but they weren’t built to resist corrosion forever. If your brakes feel spongy, don’t just change the pads—look at the brake booster and proportioning valve to make sure everything’s working as it should. Classic Parts Pro will have everything you need soon—sign up for the newsletter so you’re the first to know when parts drop!