The 1956 GMC pickup is the kind of truck that turns heads without trying. Big grille. Classic lines. And that unmistakable stance that screams mid-century utility. It’s one of those builds where the more you dig into it, the more character you uncover—but also, let’s be real, the more rusted bolts and missing parts you’ll find.

If you’re restoring or maintaining a ’56 GMC, this guide is here to give you the lay of the land. We’ll walk you through what parts commonly fail, what you should upgrade while you’re in there, and a few gotchas you’ll want to know before you crack open the toolbox.

The ’56 GMC was part of the New Task Force series that replaced the Advance Design models. What set it apart from its Chevy cousin was its stronger frames, heavier-duty components, and a different selection of engines—including some Pontiac V8s, which were rare for the time.

Fun stat: The 1956 model was the last year to feature the wraparound windshield with a vertical A-pillar—making it a one-year-only feature that restorers love (and parts hunters fear).

These trucks were built to last—but that doesn’t mean they’re immune to 70 years of wear.

Let’s start with the essentials. If you just picked one up from a field or auction, assume these parts need attention:

Braking System
The stock brakes were 4-wheel drums—simple, but not great by modern standards. Expect to replace:

• Brake shoes and hardware

• Master cylinder

• Wheel cylinders

• Brake lines (steel and rubber)

• Consider a front disc brake conversion if you plan to drive it regularly

Cooling System
Overheating is common on both the inline-6 and V8 variants. Often caused by clogged radiators or leaky hoses.
Check and likely replace:

• Radiator (many go with aluminum upgrades)

• Water pump

• Hoses and clamps

• Thermostat and housing

Fan (consider upgrading to an electric setup for city driving)

Fuel System
If the truck’s been sitting for any length of time, assume the gas tank is rusty and the pump is toast.
Start with:

• Fuel tank (consider relocating it under the bed for safety and space)

• Fuel pump

• Fuel lines

• Carburetor rebuild kit or replacement

• Sending unit and fuel filter

Suspension and Steering
You’ve probably got worn bushings, cracked leaf spring mounts, and loose steering. Welcome to the club.
Parts to plan for:

• Leaf spring shackles and bushings

• Kingpins or ball joints (depending on if it’s been swapped)

• Tie rods and drag link

Steering box (many go with a power steering upgrade)

Electrical System
From brittle wires to non-functioning gauges, electrical gremlins are common.
Replace or rewire:

• Headlight and taillight harness

• Ignition switch and fuse panel

• Voltage regulator

• Battery cables and grounds

• Consider upgrading to 12V if it’s still running 6V

If you’re lucky, your truck still has its original trim—but more often than not, you’ll need to source or restore it.

• Headlight bezels

• Grille inserts

• Badging

• Window seals and door weatherstripping

• Cab mounts (critical and often ignored)

These parts can be tough to find in good shape, but there’s still a passionate community (and a few low-key suppliers) out there with hidden stock.

Check your VIN and engine stamping—some ’56 GMCs came with factory Pontiac V8s, which means totally different parts than the inline-6 trucks.
When sourcing fenders, check Chevy compatibility—but beware: many GMC panels have subtle differences.
Don’t skip the cab corners—rust hides there even in clean-looking trucks.

The challenge with restoring a truck like this isn’t always knowing what to replace—it’s knowing where to find it. That’s where Classic Parts Pro comes in. We’re building a network of trusted suppliers and old-school shops that still stock the hard-to-find stuff—because you shouldn’t have to piece together your project from a dozen different websites.

If there’s something you’re stuck on, shoot us a message. Chances are, someone on the CPP team has fought that same bolt or found that same missing bracket.

Restoring a 1956 GMC is equal parts grit and passion. Whether you’re doing a full frame-off restoration or just keeping a family truck on the road, you’re part of something bigger—something rooted in American ingenuity and hands-on pride. Classic Parts Pro is here to back you up, part by part.