Overview#
The Blue Star JD40-05FT4 is a 40-kilowatt EPA Tier 4 Final diesel standby/prime generator built around the John Deere 3029HG530 — a compact 2.9-liter inline-three with integrated DOC/DPF exhaust aftertreatment. This is a current-production active model and the smallest Tier 4 Final unit in Blue Star's diesel lineup.
The "-05FT4" suffix indicates this is the fifth generation of the JD40 platform with Tier 4 Final emissions compliance. Unlike larger Tier 4 Final engines that require SCR aftertreatment and DEF fluid, the JD40-05FT4 achieves Tier 4 Final with DOC/DPF only — no DEF required.
The John Deere 3029HG530 platform#
The 3029HG530 is John Deere's smallest PowerTech genset engine:
- 2.9L inline-three — the most compact engine platform in the Blue Star lineup, with bore of 4.20 in and stroke of 4.30 in
- DOC/DPF aftertreatment — the diesel oxidation catalyst and diesel particulate filter are mounted as an integrated exhaust filter/silencer, replacing the separate critical-grade silencer used on Tier 3 models
- No DEF required — the DOC/DPF system handles particulate and emissions reduction without selective catalytic reduction
- 9,000 ft altitude ceiling — the best in the entire Blue Star lineup, suitable for any US installation including high-altitude mountain sites
- Equal standby and prime ratings — 40 kWe for both, allowing continuous prime power operation at full rating
Variant selection guide#
The JD40-05FT4 is Blue Star's entry-level Tier 4 Final diesel:
- JD40-03 (40 kW, John Deere, Tier 3) — the predecessor model without aftertreatment. Choose this only where Tier 3 is still permitted for the intended application.
- JD50-03 (50 kW, John Deere, Tier 3) — next step up in kW if 40 kW is marginal for the load study. No Tier 4 Final equivalent at 50 kW currently available.
- JD60-04FT4 (60 kW, John Deere, Tier 4 Final) — the next Tier 4 Final model up if more power is needed.
When to spec the JD40-05FT4#
- 30-40 kW emergency standby or continuous prime loads on diesel fuel
- Jurisdictions requiring Tier 4 Final emissions (California CARB for non-emergency, any new installation mandating T4F)
- Small commercial facilities: retail stores, restaurants, small offices, houses of worship
- Sites at any elevation up to 9,000 ft — including mountain installations
- Applications where DEF-free operation is preferred (the DOC/DPF system requires no consumable fluids beyond diesel fuel)
- Noise-sensitive locations — the 74 dBA open-skid sound level is exceptionally quiet



