Install a Soft Tonneau on a 2019-2026 GMC Sierra 1500

Quick answer

Installing a soft roll-up tonneau cover on your 2019-2026 GMC Sierra 1500 is a straightforward no-drill job. The CoveRex SR Series uses clamp-on rails and a tension system that lets you finish in under an hour.

Installation steps

1. 1. Prepare the bed and gather tools: Clean the top edge of the bed rails thoroughly. Remove any dirt or wax so the clamps grip properly. You need a socket wrench (usually 10mm), a tape measure, and the supplied hardware kit. Do not skip cleaning – grease or debris can cause the clamps to slip later.
2. 2. Attach the front header bar: Position the front header bar against the bulkhead (front wall of the bed). Use the provided J‑hooks or brackets to secure it to the bed rail lip. Tighten evenly, but do not fully torque yet. Check that the header bar sits level across the width of the bed – an uneven bar will cause the cover to sag.
3. 3. Install the side rails: Slide the side rails into the front header bar. Place the clamp assemblies over the bed rail lip at each stake pocket location. Tighten each clamp until the rail is snug but still adjustable. Do not overtighten the clamps – you want a firm grip without deforming the bed rail. If the rail shifts during the next step, loosen and reposition.
4. 4. Mount the rear bar and tension assembly: Attach the rear bar to the side rails. Install the tension cables or spring‑loaded rods that connect the rear bar to the front header. This is what pulls the cover tight. Common mistake – routing the cables incorrectly can cause the cover to bunch or flap at highway speed. Follow the cable path diagram included in the kit.
5. 5. Roll out and secure the cover: Unroll the vinyl cover from the front toward the rear. Hook the cover’s front edge into the header bar channel, then snap or Velcro the sides into the side rail grooves. Engage the rear tension mechanism. On a cool day, the vinyl may be stiff. Let it warm in the sun for 10 minutes before tensioning – this prevents over‑stretching and ensures a drum‑tight fit.
6. 6. Adjust tension and test operation: Use the tension knobs or lever at the rear to tighten the cover until it is smooth across the bed. Roll and unroll the cover once to confirm it glides freely and latches securely. If the cover is too loose, it will flap; too tight, and the vinyl may tear at the seams. Aim for a surface that is taut but still has slight give when pressed.

Product facts

• ARMORDILLO® CoveRex SR Series 2019-2026 GMC Sierra 1500 5'8" Bed Low Profile Soft Roll-up Tonneau Cover: Premium Soft Roll‑Up Truck Bed Cover with No‑Drill Installation, built with heavy‑duty black vinyl and a reinforced support frame. The vinyl resists UV and tearing, while the no-drill clamps let you install it without permanent modifications to your Sierra 1500.