Disclaimer: The fuel consumption rates listed in this guide are general reference figures based on engineering derivations and publicly available research. The actual fuel consumption for your specific vehicles and equipment may differ significantly depending on engine size and tune, hydraulic system type, RPM settings, duty cycle, load, and ambient conditions. The rates you set in the system directly affect your FTC calculations. You should use rates that accurately reflect your fleet's actual consumption. If you are unsure, consult your equipment manufacturer's specifications, your fuel records, or a qualified advisor.
When a vehicle's engine powers auxiliary equipment through a power take-off (PTO), the engine consumes fuel even though the vehicle is stationary or operating at very low speed. This fuel use may be eligible for FTC depending on the activity and location.
This guide covers common heavy truck PTO applications and the engine fuel consumption rates associated with each — expressed in litres per hour (L/hr), which is the appropriate unit when distance travelled is not the primary measure of work done.
How PTO fuel consumption works
When a PTO is engaged, the truck engine bears the combined load of idling and driving the auxiliary system. The total engine fuel consumption during PTO operation has two components:
PTO-engaged fuel (L/hr) = Base idle fuel + Additional load from auxiliary equipment
Base idle fuel consumption for a heavy diesel truck:
| Idle state | L/hr |
|---|---|
| Light idle (in park, no load) | 2–3 |
| Elevated idle (PTO warm-up or set RPM) | 3–5 |
The power demand of the auxiliary equipment determines how much fuel is added above this idle baseline. As a general rule of thumb, a typical heavy diesel engine consumes approximately 0.24–0.28 litres of diesel per kilowatt-hour (kWh) of PTO work delivered.
Equipment-by-equipment rates
Belt tipper / conveyor spreader
A truck-mounted conveyor belt that distributes gravel, aggregate, or similar materials. The belt is driven by a PTO-connected hydraulic motor.
Typical PTO power demand: 15–40 kW depending on belt width and material density.
| Operating mode | L/hr |
|---|---|
| Idle (belt off, hydraulics pressurised) | 4–6 |
| Light operation (narrow belt, light material) | 8–14 |
| Full operation (standard gravel/aggregate) | 12–20 |
| Heavy/wide belt under full load | 18–28 |
Practical working rate: 12–20 L/hr for standard operation.
Fuel and liquid tanker — PTO pumping
The PTO drives a gear or centrifugal pump to transfer liquid from the tanker to storage or vehicles. The truck engine runs at elevated idle while stationary.
Note: the fuel being pumped is transferred to the customer and is not consumed by the engine. Only the engine fuel used while the pump operates is relevant here.
Typical PTO power demand: 5–25 kW depending on flow rate and delivery pressure.
| Application | Engine L/hr consumed |
|---|---|
| Small utility/farm fuel truck | 4–8 |
| Medium tanker (general delivery) | 6–12 |
| Large tanker (aviation or terminal unload) | 8–15 |
| Idle (pump engaged but not flowing) | 3–6 |
Real-world data from a study of milk tanker PTO pumping operations found average consumption of approximately 5–6 L/hr during pumping, consistent with the low-to-mid range for moderate pump loads.
Practical working rate: 5–12 L/hr for standard liquid tanker PTO pumping.
Truck-mounted hydraulic crane / knuckle boom
A hydraulic crane mounted on a truck chassis, driven by a PTO-connected hydraulic pump. Includes knuckle boom cranes (e.g. Palfinger, Hiab) and straight-boom cranes used in logistics, construction, and utilities.
Typical PTO power demand: 15 kW (small articulating) to 150+ kW (large industrial).
| Crane size / type | Lifting capacity | L/hr during operation |
|---|---|---|
| Light knuckle boom (pickup/medium truck) | 2–5 tonne-metre | 4–8 |
| Medium truck-mounted crane | 8–12 tonnes | 15–25 |
| Heavy truck-mounted crane | 12–16 tonnes | 25–35 |
| Large industrial (tyre-mounted, 20+ t) | 20–50 tonnes | 30–50 |
| Idle (crane ready, not lifting) | — | 4–8 |
Practical working rate: 15–35 L/hr for typical truck-mounted cranes in Australian logistics and construction contexts.
Container sidelifter / straddle arm
Hydraulic lifting arms mounted on a trailer or truck chassis to self-load and unload ISO containers. The arms are driven by a PTO-connected hydraulic pump on the prime mover.
Typical PTO power demand: 40–80 kW during an active lift stroke.
| Operating mode | L/hr |
|---|---|
| Idle (hydraulics engaged, arms stationary) | 5–8 |
| Extending/positioning arms | 10–18 |
| Active lifting (loaded container) | 20–35 |
| Lowering / controlled descent | 8–15 |
| Operational average (full cycle including idle) | 15–25 |
The operational average accounts for the full duty cycle — active lifting, repositioning, and idle time between lifts.
Practical working rate: 15–25 L/hr operational average; peak during active lift up to 30–35 L/hr.
Hydraulic tailgate / tuckaway lift gate
A rear-mounted hydraulic lift gate on delivery trucks for kerb-side loading and unloading. Common in urban delivery, refrigerated transport, and LTL freight.
Typical PTO power demand: 5–15 kW — among the lowest of common PTO applications.
| Operating mode | L/hr |
|---|---|
| Idle (gate lowered, not cycling) | 3–5 |
| Active cycling (raising/lowering 500–2,500 kg) | 4–8 |
| Heavy gate, frequent cycling | 6–10 |
Lift gates are typically intermittent duty. The fuel impact is more significant in aggregate shift terms, where the dominant cost is the elevated idle while the driver operates the gate and unloads cargo.
Practical working rate: 4–8 L/hr during active operation; often averages 3–6 L/hr over a full shift due to intermittent use.
Cement mixer / transit mix truck
The rotating drum on a concrete transit mixer is driven by the truck engine via a PTO hydraulic circuit or direct drive shaft. The drum rotates both in transit (agitation) and during discharge (higher RPM, reverse).
Typical PTO power demand: 20–50 kW loaded; upper range during discharge.
| Operating mode | L/hr |
|---|---|
| Drum rotating in transit (agitation, loaded) | 10–20 |
| Drum at discharge speed | 15–25 |
| Drum stopped (waiting at site) | 3–6 |
| Full operational average (transit + pour) | 12–20 |
Practical working rate: 10–18 L/hr for a standard 7–10 m³ transit mixer during drum operation.
Concrete boom pump (truck-mounted)
A truck-mounted boom pump uses a large PTO-driven hydraulic system to pump concrete through a folding boom. Power demands are among the highest of any common PTO application due to the pumping pressures required (up to 85–160 bar).
Typical PTO power demand: 100–200+ kW during active pumping.
| Operating mode | L/hr |
|---|---|
| Idle (boom out, pressurised, not pumping) | 8–15 |
| Small boom pump (active pumping) | 10–15 |
| Medium boom pump (active pumping) | 15–25 |
| Large boom pump (active pumping) | 25–40+ |
| Overall average (pumping and idle mixed) | 18–25 |
Practical working rate: 15–25 L/hr for a standard truck-mounted boom pump.
Logging crane / hydraulic grapple loader
Many logging trucks are fitted with a PTO-driven hydraulic grapple crane that lifts and stacks logs onto the trailer. This PTO fuel consumption is separate from the driving fuel covered in the fuel consumption rates reference guide.
Typical PTO power demand: 40–90 kW during active grapple cycles.
| Operating mode | L/hr |
|---|---|
| Idle (crane ready, not swinging) | 5–8 |
| Active grapple / swing / load cycle | 20–35 |
| Operational average (loading cycle including repositioning) | 15–25 |
Practical working rate: 15–25 L/hr during loading operations.
Garbage compactor / refuse collection truck
The PTO drives a hydraulic compaction system — including the ram and blade that compress waste into the body. The compactor cycles every 20–35 seconds during active collection, and refuse trucks spend approximately half of operational time idling during stops.
Typical PTO power demand: 30–60 kW during compaction.
| Operating mode | L/hr |
|---|---|
| Idle at collection point | 4–7 |
| Compactor cycling (active collection) | 10–20 |
| Heavy-duty commercial compactor | 15–25 |
| Operational shift average (transit and collection combined) | 8–15 |
Practical working rate: 10–18 L/hr during active compaction; 4–7 L/hr at idle between stops.
Summary reference table
| PTO application | Typical power draw (kW) | Idle L/hr | Active L/hr | Practical working rate |
|---|---|---|---|---|
| Belt tipper / conveyor spreader | 15–40 | 4–6 | 12–20 | 12–20 |
| Fuel / liquid tanker pump | 5–25 | 3–6 | 6–12 | 5–12 |
| Truck-mounted crane (medium) | 30–80 | 5–8 | 20–35 | 15–30 |
| Container sidelifter | 40–80 | 5–8 | 20–35 | 15–25 |
| Hydraulic tailgate | 5–15 | 3–5 | 5–8 | 4–8 |
| Cement mixer drum | 20–50 | 3–6 | 10–18 | 10–18 |
| Concrete boom pump | 60–200 | 8–15 | 18–35 | 18–25 |
| Logging crane / grapple loader | 40–90 | 5–8 | 20–35 | 15–25 |
| Garbage compactor | 30–60 | 4–7 | 10–20 | 10–18 |
Additional common PTO applications
| PTO application | Approximate L/hr | Notes |
|---|---|---|
| Fire truck pump (split-shaft, full flow) | 25–60 | Engine at governed RPM; very high power demand |
| Vacuum tanker (liquid waste) | 10–20 | High-torque PTO vacuum pump |
| Street sweeper (fan and conveyor) | 12–20 | Continuous PTO during sweeping |
| Water / spray tanker pump | 5–12 | Similar profile to fuel tanker |
| Refrigeration unit (ePTO or shaft-driven) | 3–8 | Lower demand; often a separate auxiliary diesel |
| Aerial work platform / EWP | 8–18 | Varies with basket weight and extension |
| Tipper hydraulic ram (raise/lower cycle) | 6–15 | Intermittent — PTO active for ~30–60 seconds per tip |
| Pneumatic blower (dry bulk tanker) | 15–30 | High-RPM blower draws significant PTO power |
Factors that affect actual rates
Engine and RPM setting — Many PTO applications require elevated engine RPM (1,200–1,800 rpm vs ~700 rpm at base idle). This alone can roughly double base idle fuel consumption. Euro 5/6 engines with electronic load sensing will generally consume less than older mechanical units under equivalent PTO load.
Duty cycle — The rates above represent consumption during active PTO-engaged operation. If a crane or compactor is only active 40% of the time during a shift, the shift-average fuel rate will be substantially lower than the active-operation rate.
Hydraulic system type — Older fixed-displacement hydraulic pumps circulate oil continuously regardless of demand. Modern load-sensing systems only generate flow when needed, reducing fuel consumption by 10–25%.
Ambient conditions — In high ambient temperatures, additional engine cooling fan work can add 1–2 L/hr to engine idle consumption — relevant in Australian summer conditions.
Load and payload — Rates at the upper end of each range apply to maximum-rated loads. Lighter loads, partial fills, or intermittent operation will produce lower averages.
How to determine your specific rates
The reference figures in this guide are a starting point. The ATO expects businesses to use fuel consumption rates that are fair and reasonable for their specific circumstances. For PTO and auxiliary equipment, the ATO explicitly recognises several methods for establishing rates, and businesses should keep documentary evidence that the rate used is reasonable and applicable to their equipment.
Live fuel consumption testing
The ATO explicitly endorses live testing as an acceptable method for PTO equipment. The general approach for auxiliary equipment is:
- Record the starting fuel level (fill to full or record a dipstick reading).
- Operate the auxiliary equipment under normal working conditions for a representative period — for example, a defined number of lift cycles, pump hours, or compaction runs.
- Refuel (or take another dipstick reading) to determine exactly how much fuel the engine consumed during that period.
- Divide total consumption by operating hours or number of activity cycles to derive an L/hr rate.
The ATO notes that tests must account for variables affecting consumption, including vehicle age and model, engine tune, the type and load of the auxiliary equipment, and ambient conditions. Retain records of the test conditions and results as supporting evidence.
Engine Control Module (ECM) / engine diagnostic reports
The ATO explicitly accepts ECM and engine diagnostic data as a valid method for PTO fuel consumption. PCG 2016/11 states that businesses may use "actual fuel consumption data of the auxiliary equipment if it uses a power take-off connected to the module, such as engine diagnostic downloads."
Engine diagnostic reports for PTO-equipped vehicles can provide:
- PTO fuel consumption rate (L/hr while PTO is engaged)
- Idle fuel consumption rate (L/hr at base idle)
- PTO engagement hours for defined periods
- Average PTO fuel as a percentage of total engine fuel use
These figures can be used directly to set a rate or to apportion total fuel between driving and auxiliary equipment use.
Fuel consumption comparison (with and without PTO)
Where ECM data is not available, the ATO accepts a comparison approach: measure vehicle fuel consumption over equivalent periods with and without the auxiliary equipment operating. The difference represents the net fuel attributable to the PTO equipment. This is effectively a structured live test using normal operations rather than a controlled test run.
Manufacturer's specifications
Manufacturer-published data on auxiliary equipment power draw and fuel consumption is an acceptable input, particularly where live testing or ECM data is not available. Keep in mind that manufacturer figures are measured under controlled conditions and may differ from real-world consumption under variable load, temperature, and duty cycle.
Hours-based method
If you keep records of PTO operating hours (many modern vehicles log this automatically), you can establish an average hourly fuel consumption rate and apply it to hours of PTO use. The ATO accepts this approach where the rate is derived from a sample period that accurately reflects normal operations, and where the sample is reviewed if operating conditions change materially.
ATO guidance references
- Powering auxiliary equipment
- PCG 2016/11 — Apportioning taxable fuel used in a heavy vehicle with auxiliary equipment
- Calculating eligible fuel quantities