Overview#
The Kohler 145REOZT4 is a 130-kilowatt standby (117 kW prime) EPA Tier 4 Final diesel mobile trailer generator powered by a John Deere 6068HG550 engine at 1800 RPM. The 6-cylinder, 6.8-liter John Deere engine is paired with a Kohler 4R13X brushless rare-earth permanent-magnet alternator (Fast-Response X) and the Decision-Maker 3500 paralleling controller, making this unit suitable for both standalone large temporary power needs and synchronized multi-unit parallel deployments.
At 130 kW standby, the 145REOZT4 occupies the mid-range of the REOZT4 trailer lineup — above the 85 kW 90REOZT4 and below the 150 kW 175REOZT4. Both the 145REOZT4 and 175REOZT4 share the same 6068HG550 engine and the same 150.9" x 46.8" x 90.3" enclosure dimensions, differing primarily in alternator selection. The 145REOZT4 uses the 4R13X alternator while the 175REOZT4 uses the larger 4S12X.
The unit requires DEF (Diesel Exhaust Fluid) via an SCR system for Tier 4 Final compliance. A 1,045-liter (276-gallon) integral diesel tank and 44.2-liter (11.7-gallon) DEF tank provide 24-hour runtime at prime rating. The dual-axle trailer is rated at 6,000 lb. per axle, DOT and Transport Canada compliant. Sound level is rated at 70 dB(A) at 7 meters.
Specifications#
| Spec | Value |
|---|---|
| Standby Power | 130 kW |
| Prime Power | 117 kW |
| Voltage | 120/208V, 120/240V, 277/480V, 347/600V |
| Frequency | 60 Hz |
| Engine | John Deere 6068HG550 |
| Cylinders | 6 inline |
| Displacement | 6.8 L (415 cu. in.) |
| Aspiration | Turbocharged, Charge Air Cooled |
| Emissions | EPA Tier 4 Final (nonroad, SCR+DEF) |
| RPM | 1800 |
| Alternator | Kohler 4R13X |
| Fuel | Ultra Low Sulfur Diesel / HVO / RD |
| Cooling | Liquid (unit-mounted radiator, 50°C ambient) |
| Fuel consumption — 75% load | 7.2 gph (standby) |
| Fuel consumption — 100% load | 9.4 gph (standby) |
| Diesel tank | 276 gal (1,045 L) — 24 hr minimum runtime |
| DEF tank | 11.7 gal (44.2 L) |
| Sound level | 70 dB(A) @ 7 m (prime, full load) |
| Dimensions (L x W x H) | 150.9" x 46.8" x 90.3" |
| Controller | Decision-Maker 3500 |
Service & Maintenance#
Kohler's published maintenance schedule for the 145REOZT4 / John Deere 6068HG550 engine:
| Service | Interval |
|---|---|
| Oil and filter change | Every 250 hours or 12 months |
| Fuel filter replacement | Every 500 hours |
| Air filter inspection/replacement | Every 500 hours |
| Coolant flush | Every 3,000 hours or 5 years |
| DEF system inspection | Per John Deere/Kohler schedule |
| Load bank test | Every 12 months (NFPA 110 requirement) |
| Major overhaul | Every 15,000 hours |
The John Deere 6068HG550 oil pan holds 28.5 liters (30.1 quarts) with filter. The 24-volt starting system uses two 400 CCA batteries (12V each). DEF quality and SCR system health should be verified at each service call. Recommended DEF is AUS32 per ISO 22241-1.
Common Failure Modes#
The 145REOZT4 uses the John Deere SCR/DEF system for Tier 4 Final compliance. DEF quality alerts and NOx sensor faults are the most common issues in this power class; low-quality DEF or contaminated DEF tanks trigger derate warnings. The SCR catalyst itself typically lasts well beyond 10,000 hours in properly maintained units, but units run on poor-quality fuel or subjected to extended light-load cycles are more susceptible to deposit buildup.
Turbocharger wear presents as power loss under load and elevated exhaust smoke, typically after 12,000+ hours. Fuel quality degradation — injector fouling from stale or contaminated diesel — is a recurring issue for trailers that sit idle between deployment seasons. Battery failures (dual 12V, 400 CCA) require monitoring; replace on a 3–4 year cycle.
Our service experience#
OnPoint Generators provides installation, maintenance, load bank testing, and emergency service for Kohler industrial generators throughout Northern California and the Central Valley. The 145REOZT4 is commonly deployed for planned utility outages at large commercial facilities and as bridge power for construction projects requiring more than 85 kW of mobile capacity. The John Deere 6068 engine is well-supported regionally, and parts availability through both the Kohler/Rehlko network and John Deere distributors makes emergency service logistics straightforward.
FAQ#
What engine powers the Kohler 145REOZT4?#
The 145REOZT4 uses a John Deere 6068HG550 diesel engine — a 6-cylinder, 6.8-liter turbocharged and charge-air-cooled engine running at 1800 RPM with a maximum output of 150 kW (201 HP).
Is the 145REOZT4 EPA Tier 4 Final certified?#
Yes. The 145REOZT4 is Tier 4 Final EPA-certified for nonroad applications. It uses SCR with Diesel Exhaust Fluid (DEF) to meet NOx limits. A dedicated DEF tank and quality sensor are integrated into the unit.
Does OnPoint service the Kohler 145REOZT4?#
Yes. OnPoint Generators provides maintenance, repair, and load bank testing for Kohler REOZ diesel generators throughout Northern California, including the 130 kW class. Contact us for preventive maintenance contracts or emergency service.
