Matching a PTO to Your Transmission: Allison, Eaton Fuller, Fast Gear, ISUZU and Mitsubishi
Quick answer: A PTO is matched to the transmission, not to the truck. The three things that decide fitment are the transmission's PTO pad, the bolt pattern on that pad, and the output interface you need. Identify the transmission family first — Allison, Eaton Fuller, Fast Gear, ISUZU, Mitsubishi and others each present different pads — then confirm the numbers.
Fitment starts at the gearbox
Manufacturers fit more than one transmission to the same vehicle model and year. Fleet buyers spec automated manuals; municipal buyers spec full automatics. So two identical-looking trucks can need two different PTOs. The transmission data plate is the only reliable starting point.
Identify the transmission
- Read the data plate on the gearbox housing — make, model and build code.
- Locate the PTO opening and count the mounting holes.
- Measure the pad and check the shaft interface at the opening.
- Note the output side — where the pump or driveline will sit.
- Record the control already available in the vehicle.
With those five recorded you can specify a PTO by number instead of by hope.
Fitment notes by transmission family
| Transmission family | What to confirm | Typical application |
|---|---|---|
| Allison automatics | PTO provision on the converter or main housing, pad pattern and the specific model designation | Refuse, fire apparatus, transit and municipal vehicles |
| Eaton Fuller manuals and automated manuals | Whether the PTO opening is on the main or auxiliary case, plus bolt pattern | Long-haul, tipper and vocational trucks |
| Fast Gear (China-market) gearboxes | Model and series, plus the pad pattern used on that variant | Heavy tipper and construction trucks |
| ISUZU and Japanese-family transmissions | Pad pattern and output interface; model codes vary between ISUZU and GIGA designations | Medium trucks, tippers, utility and service vehicles |
| Mitsubishi transmissions | Model and pad pattern, and whether the unit needs a left or right-side output | Medium commercial and specialised vocational bodies |
| Scania and European heavy trucks | Transmission designation and the specific PTO interface used on that model | Heavy haulage and European fleet service |
Output interface: the second gate
Once the pad side is settled, the output side decides the rest. Direct-mount units carry the pump on the PTO flange; shaft-output units drive a remote pump through a driveline. Either way, the flange pattern and drive type must match the pump you intend to run.
Control method: the third gate
Air engagement dominates heavy truck applications. Cable suits low-volume builds. Electric control pairs with modern fleet interlocks and cab electronics. The PTO housing must be provisioned for the control you choose — this is a specification, not an accessory.
Altitude, heat and duty: the specs people forget
Two more factors decide whether the unit survives:
- Oil supply and cooling. Sustained circuits need a route for heat to leave. A PTO that never gets a break will find the weakest point in the system.
- System pressure. Higher working pressure raises torque through the PTO. The pump's pressure setting is part of the PTO specification.
Frequently asked questions
Can I fit a PTO to any automatic transmission?
Only if the transmission is offered with a PTO provision. Many automatics do provide one, but the pad pattern and permitted torque differ by model, so the specific designation must be checked.
Do I need a different PTO for a manual versus an automatic?
Usually yes, because the PTO opening, pad and available space differ. Some families share patterns across variants, which is exactly why number-based confirmation matters more than assumptions.
My transmission has two PTO openings — which do I use?
Choose based on required output direction, ratio and clearance. The two openings often provide different ratios and rotation, so the choice affects pump speed and hose routing.
What information do I need to order the right PTO first time?
Transmission make and model, PTO pad bolt pattern, existing PTO part number, required output type and flange, control method, and the pump's displacement and working pressure.
Can a PTO be fitted later, after the vehicle is built?
Yes, in many cases. The body builder or workshop fits the PTO after chassis delivery. The constraint is pad availability and space, not the order of assembly.
Find the right unit
Browse PTO assemblies by transmission family and application: truck & commercial, the full PTO range, or start from application notes.
Need help confirming fitment? Send us your transmission model, the PTO number on your current unit, and a photo of the mounting pad. We check bolt pattern, shaft interface and torque rating before you buy — contact the KT Auto Parts team.
KT Auto Parts supplies new aftermarket replacement parts. All brand and model names are used for reference and identification purposes only and remain the property of their respective owners.