GMC G15/G1500 Van Parts & Accessories

GMC G15/G1500 Van Parts & Accessories

The GMC G15/G1500 Van collection covers the full production span of the GMC half-ton full-size van, from the original G15 designation of the 1970s through the G1500 naming used in the later model years on the same G-body platform shared with the Chevrolet G10 and G1500. Both designations refer to the same class of half-ton full-size van, with the naming transition reflecting GM's broader effort to standardize alphanumeric designations across its truck lineup in the 1980s and 1990s. Engine options evolved through the production run from carbureted inline-sixes and small-block V8s to fuel-injected options including the throttle-body injected 5.7 Vortec in the later G1500 years, all of which have strong parts availability. The G-body van platform serves restoration, conversion, and performance builds with consistent parts support across the entire production run.

Popular Upgrades

For earlier carbureted G15 vans, Edelbrock Performer intake manifolds and Holley carburetors on the 350 small-block provide the most meaningful power and drivability improvement from a bolt-on combination. Later fuel-injected G1500 vans benefit from K&N cold air intakes and Flowmaster or Borla cat-back exhaust systems that improve throttle response and add exhaust sound quality to the 5.7 TBI and Vortec engines. Front disc brake conversion kits are the most important safety upgrade across all G15 and G1500 van years, replacing the factory four-wheel drum setup with modern front rotor and caliper hardware that provides substantially better stopping capability.

Performance and Handling

The G-body platform uses a front coil spring suspension with a solid rear axle on leaf springs, which is mechanically simple and responds well to fresh shocks from Monroe or Bilstein, new control arm bushings, and proper wheel alignment that restores confident straight-line tracking. Power steering maintenance is critical on any high-mileage G-body van because the hydraulic system components experience wear that increases effort and introduces vagueness into the steering feel, and a rebuilt or replacement pump and steering gear restores the light, easy steering that makes these large vans pleasant to drive. Rear spring packs from National Spring or SuperSprings restore load capacity on vans that have sagged from years of heavy payload use in commercial or conversion service.

What engine options were available in the G1500 compared to the G15?

The G15 used carbureted engine options from the 250 cubic inch inline-six through the 350 small-block V8 with Rochester two-barrel or four-barrel carburetors depending on the year and option package. The G1500 transitioned to throttle body fuel injection with the 4.3 V6 and 5.7 TBI V8 before the Vortec upgrade arrived in the mid-1990s with central port injection that significantly improved fuel economy and cold-start behavior. Parts for the TBI and Vortec engines are standard GM fare and are widely available through automotive parts stores alongside the earlier carbureted engines' parts, so the entire G15 through G1500 production run is well-supported regardless of model year.

What is the best exhaust upgrade for a G1500 with the 5.7 Vortec?

The most popular exhaust approach for the 5.7 L31 Vortec G1500 van is a single-exit cat-back system with a Flowmaster 40-series or Magnaflow muffler that replaces the factory muffler and rear pipe without requiring header changes. Long-tube headers are available for the van application but require more clearance work in the engine compartment than the same headers on a pickup, making shorty headers from Hedman or Hooker a more practical choice for vans where under-hood access is tighter. The combination of shorty headers and a cat-back exhaust delivers a full exhaust upgrade with improved tone and modest power gains that complement the Vortec engine's mid-range torque character.

Why These Parts Fit Right

Parts in the G15/G1500 collection are verified across the full G-body half-ton van production run with year-specific and engine-specific fitment noted for both carbureted and fuel-injected configurations. Cross-reference between G15 and G1500 designations is noted to maximize available parts from suppliers that catalog under either name. Most in-stock parts ship same day or next business day.

Related resources include the exhaust systems collection, the suspension parts catalog, and the air intake systems section.