Fiberglass Truck Caps – Lightweight, Durable Protection for Your Pickup
Our fiberglass truck caps deliver the perfect balance of strength and weight savings for daily drivers and weekend adventurers alike. Built from reinforced composite fiberglass, each cap ships with a smooth gel-coat finish that resists UV damage and maintains color for years. We engineer every model to integrate seamlessly with your truck’s factory bed rails, with available height profiles to accommodate different cargo needs.
Whether you’re securing tools for the job site or protecting camping gear on the highway, a fiberglass cap adds lockable storage without the weight penalty of steel alternatives. Every unit includes weather-stripping along all four sides, tinted sliding side windows, and a full rear door with integrated glass and locking hardware.
- Reinforced composite fiberglass shell with UV-resistant gel-coat finish
- Tinted sliding side windows with aluminum frames and screens
- Full rear door with integrated tempered glass and three-point locking system
- Factory color-match options available for most truck makes and models
- Height profiles from standard to high-roof configurations
Fiberglass construction & finish quality
We mold every fiberglass truck cap from multiple layers of woven fiberglass mat saturated with polyester resin, then cure the shell in climate-controlled tooling to eliminate voids and ensure consistent wall thickness. The outer gel-coat layer goes on before demolding, creating a smooth, paint-ready surface that requires no additional sealing.
This composite construction delivers impact resistance superior to ABS plastic while weighing roughly 30 percent less than equivalent steel caps. The gel-coat finish resists stone chips, minor abrasions, and UV degradation without the maintenance cycle required by painted aluminum alternatives. For customers who prioritize a factory-fresh appearance, we offer color-match services for most domestic and import truck models, applying automotive-grade paint over a bonded primer coat.
Window & ventilation options
Every fiberglass cap ships standard with tinted sliding side windows on both driver and passenger sides. Each window rides in an extruded aluminum track with integrated screen panels, allowing you to secure ventilation without compromising bed security. The tempered glass panels lock in the closed position via cam latches accessible only from inside the cap.
The rear door assembly integrates a large sheet of tempered safety glass with a three-point rotary locking system keyed to match your truck’s ignition. We seal the door perimeter with EPDM rubber bulb weatherstripping that compresses against the cap’s rear flange, maintaining a watertight seal even during high-pressure car washes. An optional electric rear window defroster grid can be factory-installed for cold-climate operators who need year-round rear visibility.
Mounting & bed compatibility
Installation hardware
Our fiberglass caps mount directly to your truck’s factory bed rails using stainless steel C-clamps and rubber isolation blocks. The clamp assemblies thread through pre-drilled holes in the cap’s lower flange, allowing you to torque each fastener to our recommended specification without risking gel-coat cracks. We include enough clamps to position one every twelve inches along both bed rails, ensuring even load distribution and eliminating flex during highway driving.
Bed length & height configurations
We manufacture fiberglass caps for standard bed, short bed, and long bed configurations across all major truck platforms. Height options range from our low-profile model—which sits flush with the truck’s cab roofline—to our high-roof variant that adds sixteen inches of interior clearance for bulky cargo. Each cap ships with a vehicle-specific fit guide detailing proper clamp placement and torque values for your exact make, model, and bed length.
Complete your truck bed system
What people are saying
Common questions about fiberglass caps
Most fiberglass truck caps weigh between 150 and 220 pounds depending on bed length and height configuration. A standard-height cap for a six-and-a-half-foot bed averages around 180 pounds, while high-roof models add another 30 to 40 pounds due to increased surface area and reinforcement. This makes fiberglass caps roughly 30 percent lighter than equivalent aluminum models and 50 percent lighter than steel caps.
Yes, fiberglass caps accept automotive paint extremely well due to their gel-coat surface. We recommend sanding the gel-coat with 320-grit paper to create mechanical adhesion, then applying a bonding primer before your color coats. Many body shops offer color-match services using your truck’s paint code. Alternatively, we provide factory color-matching for most popular truck colors at the time of purchase.
Fiberglass caps typically improve highway fuel economy by one to two miles per gallon compared to driving with an open bed. The cap eliminates the turbulent air pocket that forms behind the cab, reducing aerodynamic drag at speeds above 45 mph. However, the added weight of 150 to 220 pounds may slightly reduce acceleration and fuel economy during stop-and-go city driving.
Fiberglass composite construction performs well across temperature extremes from minus 40 to plus 120 degrees Fahrenheit. The material does not rust, corrode, or require seasonal maintenance like painted metal alternatives. UV-resistant gel-coat finishes maintain color and gloss for years without fading. In high-heat environments, ensure adequate ventilation through side windows to prevent heat buildup inside the cap.
Most fiberglass caps support aftermarket roof rack systems when properly reinforced. We offer factory-installed backing plates and threaded inserts in the cap ceiling that distribute rack loads across a wider area, preventing stress cracks. Avoid drilling directly through the fiberglass without backing plates, and limit roof loads to 150 pounds static weight for standard-height caps and 200 pounds for reinforced work-cap models.
Our fiberglass truck caps include a three-year limited structural warranty covering defects in materials and workmanship. This covers delamination, gel-coat cracking, and hardware failures under normal use. The warranty does not cover damage from accidents, improper installation, unauthorized modifications, or cosmetic issues like minor scratches. Window glass and weatherstripping carry a one-year warranty from the date of purchase.
Removing a fiberglass cap requires loosening eight to twelve clamp assemblies along the bed rails, then lifting the cap straight up with at least two people. The process takes about fifteen minutes with basic hand tools. We recommend marking clamp positions with tape before removal to simplify reinstallation. Some truck owners install quick-release clamp systems that allow cap removal in under five minutes without tools.