Image courtesy of Knapheide.com
Your truck works hard, so the service body you put on it matters more than most people think. Pick the wrong material and you may end up hauling unnecessary weight, fighting rust every winter, or dealing with dents and damage that sideline your truck.
Here’s a plain-language breakdown of what steel, aluminum, and fiberglass service bodies each bring to the table.
Steel Service Bodies
Best for: heavy-duty jobs, construction, utilities, and anywhere durability is non-negotiable.
Steel is what most people think of first — and for good reason. It’s strong, it handles heavy loads without complaint, and if something goes wrong in the field, a welder can fix it. For contractors, utility crews, and anyone running trucks hard on rough job sites, steel holds up where other materials may not.
What to know about steel service bodies:
- Handles high-weight payloads without issue
- Impact-resistant and easier to repair after damage
- Lower upfront cost than aluminum
- Heavier than aluminum, which can affect fuel economy
- Needs proper coating or treatment to help prevent rust over time
If raw toughness is the priority, steel is still the go-to.
Aluminum Service Bodies
Best for: fleets focused on fuel savings, corrosion resistance, and long-term value.
Aluminum has come a long way, and it has become the first call for many municipal fleets, utility companies, and road maintenance operations — especially in the Midwest, where road salt is a fact of life. It won’t rust, it’s significantly lighter than steel, and over the life of a truck, the maintenance savings can add up.
What to know about aluminum service bodies:
- Can weigh up to 50% less than a comparable steel body
- Naturally resists corrosion with no coating required
- Low-maintenance over the long haul
- Higher purchase price upfront
- Not quite as impact-resistant as steel in high-abuse environments
For operators who are thinking about total cost of ownership rather than just sticker price, aluminum is often the better long-term choice.
Fiberglass Service Bodies
Best for: light- to medium-duty service work where appearance matters.
Fiberglass doesn’t get talked about as much, but it can be a solid choice for telecom, HVAC, and utility service fleets where the truck is customer-facing. It has a clean, uniform look that takes paint and branding well, and it won’t rust. The construction also offers some natural insulation, which helps protect tools and sensitive equipment from temperature swings.
What to know about fiberglass service bodies:
- Completely corrosion-proof and weather-resistant
- Lighter than steel and sturdy enough for most service applications
- Smooth, paintable surface for fleet branding
- Not the right fit for heavy loads or high-impact work
- Repairs require different techniques than metal bodies
If your trucks are rolling billboards as much as they are work vehicles, fiberglass is worth a serious look.
Service Body Material Comparison
| Material | Where It Shines | Best Fit |
|---|---|---|
| Steel | Maximum durability and repairability | Heavy-duty fleets, construction, utilities |
| Aluminum | Light weight, corrosion resistance, long-term ROI | Municipal, general service, maintenance fleets |
| Fiberglass | Clean finish, weather resistance, branding potential | Light-duty service, telecom, HVAC |
Not Sure Which Service Body Is Right for Your Truck?
We’ve been putting trucks to work across Illinois and the Midwest for decades. Whether you’re outfitting one truck or a whole fleet, we can walk you through the options and help you land on the right setup for your workload.
Give us a call at 217-753-3871 or contact us here to talk through your next upfit project.
