Silverado Medium Duty and the Isuzu-built LCF put GM iron in the same vocational space as the F-650. GDS2 plus SPS programming through the MDI 2 is the factory stack — affordable, well-documented, and often already familiar to shops with automotive backgrounds.
GM (Medium-Duty) coverage: engines, models and systems
Our GM (Medium-Duty) diagnostic coverage spans every current platform and the legacy fleets still on the road. The table below maps the engines and vehicle families you can scan, code and program with a dealer-level setup. If your truck is missing, run it through the compatibility checker or ask us on WhatsApp — coverage updates land monthly.
| Platform | Engines / Systems | Model Years | Dealer Software | Required Adapter |
|---|---|---|---|---|
| Silverado 4500–6500 HD | 6.6L Duramax L5P | 2019–2026 | GDS2 + SPS | MDI 2 / J2534 |
| Low Cab Forward (LCF) | 6.6L gas / 5.2L diesel (Isuzu) | 2016–2026 | GDS2 (+ IDSS for diesel) | MDI 2 |
| Savana / Express cutaway | 6.6L Duramax, 6.6L gas | 2011–2026 | GDS2 | MDI 2 / J2534 |
| Legacy Duramax | LB7–LMM 6.6L | 2001–2010 | GDS2 / Tech 2 | MDI 2 / Tech 2 |
OEM software vs multi-brand: which GM (Medium-Duty) setup fits your shop
GDS2 (Global Diagnostic System 2, $695/yr with SPS programming access) covers diagnostics, bi-directionals and module programming across the medium-duty line. Diesel LCF trucks additionally need Isuzu IDSS for engine-side depth — we bundle both for LCF fleets.
Shops that only touch GM (Medium-Duty) iron get the most depth per dollar from the OEM package. Mixed fleets usually pair one OEM license with a multi-brand platform — see the OEM vs aftermarket capability breakdown before you spend.
What it costs — real numbers, not “call for price”
GDS2 subscription with SPS: $695/yr. Genuine MDI 2: $795. Complete kit: $2,295. J2534 passthru works for SPS programming on most modules — see the adapter page for verified-compatible devices.
Guides and fault codes for GM (Medium-Duty)
Start with the procedures and reference pages below — they are written by working technicians and kept current with each software release.
- Forced DPF regen master guide — L5P Duramax procedure.
- ECM programming guide — SPS via J2534.
- Ford medium-duty hub — the cross-shop alternative.
- Isuzu hub — for LCF diesel engine work.
GM (Medium-Duty) kits & best-sellers
GM GDS2 + MDI 2 Kit
GDS2 + SPS subscription + genuine MDI 2 with remote install.
View details →Genuine MDI 2 Interface
GM's factory VCI for GDS2 diagnostics and SPS programming.
View details →Frequently Asked Questions
Does GDS2 cover the Isuzu-built LCF diesel engine?
GDS2 covers chassis and body systems on the LCF; the 5.2L 4HK1 diesel engine requires Isuzu IDSS for full engine diagnostics. We bundle GDS2 + IDSS for LCF fleets at a package discount.
Can I program GM modules with a J2534 passthru?
Yes for most modules via SPS — GM has the most J2534-friendly programming ecosystem of any OEM. The MDI 2 remains the safest choice for security-related and high-voltage modules.
Is GDS2 the same as the old Tech 2?
No — Tech 2 covers pre-2011 vehicles. GDS2 covers 2011+ and both coexist for mixed-age fleets. Most Duramax work from LML onward is GDS2 territory.