ZF Marine Gearbox
& Thruster Spare Parts
Reverse-reduction gearboxes · hybrid PTI transmissions · AT and TT thrusters · propulsion controls — quoted from the type plate
The ZF propulsion equipment behind engine-room enquiries
ZF Friedrichshafen AG runs its marine business from product competence centres in Friedrichshafen, Krimpen aan de Lek and Padova. On a commercial ship an enquiry usually concerns one of three things: the reverse-reduction gearbox between the engine and the propeller shaft, a thruster, or the control system that shifts the gearbox and sets engine speed. ZF writes its designations as a number followed by suffix letters, and its own lubricant list treats those letters as separate variants, so the full string from the plate is where identification starts.
ZF W17200 · ZF W340
ZF presents ToughGear as cast-iron transmissions for continuous duty on tugs, ferries, offshore support vessels, fishing vessels and other workboats, with PTO, PTI and PTH options, AutoTroll for manoeuvring and positioning, and rotation concepts listed as CEW and CCEW. ZF's lubricant list covers W-prefixed units from ZF W220 upwards with variant letters C, NR, NC, DS and NR2H. Clutch plate sets, seals, bearings, filters and cooler elements are matched to the serial.
ZF 2050 · ZF 60000 NR2H
ZF gearboxes without the W prefix; ZF's own list of commercial installations includes the ZF 2050 and the ZF 60000 NR2H. ZF's lubricant list groups the types from ZF 220 to ZF 83700 with suffix variants such as A, V, IV, C, U, D, NC, NR, NR2H and TS, and its hybrid range uses the A suffix for a down-angle unit. ZF data sheets rate a gearbox separately for each duty class, so the duty of the installation and the parts list number on the plate decide clutch, bearing and seal items, not the type number alone.
ZF 3300 PTI · ZF 8300 PTI · ZF 3000 NRD PTI
Gearboxes with a power take-in for an electric motor, listed by ZF for FPP, CPP and waterjet propulsion, in cast iron or light alloy housings, in parallel, A and V configurations and with DR and DL reversing layouts. ZF also supplies complete systems with flexible couplings, electric pumps, inverters and control units. The PTI and its clutch are quoted as separate lines.
ZF 400 IV · ZF 4 to ZF 115
ZF builds its small-medium range, shown with the ZF 400 IV, in a sea-water resistant aluminium alloy housing for pleasure craft as well as commercial duty cycles. Within it, the mechanically operated M-series is also used in lifeboats, the TS series is a two-speed design, and higher-rated models carry ZF's SuperShift2 clutch control. ZF's lubricant list groups the smallest numbered types, ZF 4 to ZF 115, with variant letters including M, A, IV and TS. Because ZF names lifeboats among the uses, such a gearbox can be found aboard a merchant ship as well as on small craft.
BW · HBW · HSW · IRM
Plates reading BW, HBW, HSW or IRM instead of a ZF-prefixed type are covered by ZF's current lubricant list alongside its own ranges. They are identified the same way — type, serial number and, where stamped, the parts list number — and items are matched to that serial rather than to a newer model.
ZF AT 80 · ZF AT 110 · ZF AT 6000 WM-FP
Well-mounted azimuth thrusters that combine propulsion and steering in one unit, built as L- or Z-drives with an open fixed-pitch propeller or one in a nozzle, and driven by diesel, electric, hydraulic or hybrid input. A diesel-driven unit carries an upper gearbox with a dry or wet slipping clutch, and for the wet clutch ZF points to the operating manual of that clutch variant for its lubricant. ZF's lubricant list names AT variants WM, RT, DM and SM, and ZF's reference installations write them together with the propeller type, as in ZF AT 6000 WM-FP.
ZF TT 3000 FP · ZF TT 4000 CP · ZF TT 5000 CP
Tunnel thrusters with a fixed or controllable pitch propeller, as L- or Z-drives with diesel, electric or hydraulic drive, in a flanged construction that lets the thruster be removed without dry docking. On the CP units ZF treats the power pack, lower gearbox and header tank as one oil compartment, so a seal or oil question concerns the whole circuit.
TotalCommand · ClearCommand · MicroCommand · JMS
ZF describes TotalCommand as the successor to ClearCommand and MicroCommand; it controls the engines, transmissions and thrusters of a shaft-line vessel together and also works with mechanically actuated engines and gearboxes. JMS joystick control regulates engine speed and transmission engagement through automatic trolling valves. Control heads and actuators are matched to the system generation on board.
Where a ZF marine gearbox gives trouble first
Most gearbox enquiries trace back to the clutches, the oil circuit or the cooler. Thrusters add their own oil and seal points, and ZF's documents say plainly which ones.
Hydraulically actuated multi-disc clutches
ZF's data sheet for the W325 describes a reverse reduction transmission with hydraulically actuated multi-disc clutches, and ZF Padova's operating manual for the 325 TS warns that reversing repeatedly with the engine at maximum speed considerably shortens clutch life. Slip under load, late engagement or low clutch oil pressure point to the plates, the piston seals or the rotating sealing rings that feed them, and all three are inspected together.
Water in thruster oil
In its notes for azimuth and tunnel thrusters, ZF's lubricant list has the oil checked by a laboratory at regular intervals and sets two limits for water: above the first, change the oil soon and check the rise weekly; above the second, change it at once, and ZF strongly advises stopping the unit. The laboratory report decides, and the seals are inspected before the oil is simply renewed.
Heat exchanger, filter cartridge, suction filter
ZF Padova's manual for the 325 series lists a dirty heat exchanger under troubleshooting and calls for the suction filter to be inspected and cleaned and the oil filter cartridge replaced at set intervals. A fouled cooler or a blocked filter usually shows first as rising oil temperature or sagging clutch oil pressure.
Breather and gasket weeping
ZF Padova's manual notes that too much oil can leak out through the gaskets and the breather and considerably raise running temperature. Before a gasket set is ordered for a weeping gearbox, the level is checked the way the operating manual prescribes.
Output thrust bearing
ZF designs the output shaft thrust bearing of its small-medium range, and of the W325, to take maximum propeller thrust ahead and astern. Noise that changes with propeller load, or axial movement at the output flange, points first to this bearing.
Propeller and steering pipe seals
ZF requires every seal in a thruster unit, the propeller and steering pipe seals above all, to be renewed together with the lubricant filter when the unit changes to biodegradable oil, and keeps a separate lubricant class for propeller shaft seal monitoring. A seal kit for an AT or TT unit is therefore quoted together with the oil the unit runs on.
ZF gearbox and thruster components that reach an RFQ
The groups follow a ZF gearbox from input flange to output flange, then the oil circuit, then the add-on units. Each line can carry the position number from the ZF parts list beside the description.
- Clutch plate sets — friction and steel discs
- Clutch pistons, piston seals and rotating sealing rings
- Input and output shaft bearings, including the output thrust bearing
- Radial shaft seals, O-rings and housing gasket sets
- Oil pump and shift valve components
- Solenoid valves on electrically shifted and two-speed TS units
- Trolling valve components for AutoTroll and JMS installations
- Oil filter cartridges and suction strainers
- Oil cooler elements and cover gaskets
- PTO and PTI clutch and drive components
- Control heads and actuators for TotalCommand, ClearCommand and MicroCommand
- Thruster seal kits, upper gearbox clutch parts and CP power pack items
What the ZF type plate tells a buyer
ZF Padova's operating manuals show the identification plate fixed to the gearbox itself and warn that it must not be altered or removed. The plate shown for the ZF 325 TS carries the type, serial number, parts list number, customer number and ratio, a rating for the light, medium and continuous duty classes, and the oil type and capacity; ZF's lubricant list adds that oil change intervals are given in the operating instructions and/or on the type plate. A photograph of the whole plate, taken square-on, answers most of the points below.
- Complete type designation with every suffix letter, for example NR, NR2H, A, V, IV, TS or PTI
- Serial number, and the year letter where the plate carries one
- Parts list number (PART LIST No), which fixes the build behind the type
- Customer number, where the plate carries one
- Ratio exactly as stamped
- The duty-class rating column that matches the installation
- Oil type from the plate, or the lubricant class from ZF's TE-ML 04 list
- PTO, PTI or trolling valve fitted, with its own plate data
- Control system on board: TotalCommand, ClearCommand, MicroCommand, JMS or mechanical cable
- For thrusters: AT or TT designation, variant letters, FP or CP, L- or Z-drive and the prime mover
Tools for this equipment: the lubricant code reader for the gear oil and the oil cleanliness code reader for an oil analysis report. For the torque and output speed at the gear ratio, the shaft torque calculator works from the engine power and speed.
Supply route review for ZF gearboxes and thrusters
ZF plates carry a parts list or transmission part number as well as the type, so two gearboxes with the same type name are not assumed to share clutch, bearing and seal items. The parts list number and the serial are settled first, and the supply route is chosen line by line after that.
Parts list number before part numbers
Where the plate shows a parts list number, that number, not the type name, is what item numbers are checked against. Where it has worn off, the serial number and a photograph of the removed part are the next evidence, together with an earlier order line for the same unit if the ship has one.
Classed gearbox or ship's spare
A gearbox on a propulsion line under class survey, or a repair a surveyor will inspect, is quoted on the ZF reference. Bearings, O-rings and shaft seals that carry their own makers' markings can also be reviewed on an equivalent-source path for the ship's own spares, as far as the buyer's own list of accepted sources allows.
Clutch work as one scope
Plates, piston seals, sealing rings, the filter and the gasket set that closes the housing are read as one overhaul scope, so the job is not held open by a missing O-ring. If the enquiry asks only for plates, the reply names the seals that the parts list puts in the same group instead of adding them to the line count unasked.
Cooler and oil on the same list
Where water in the oil caused the damage, the oil cooler elements and gaskets go on the same enquiry as the clutch parts. If the cooler on the gearbox carries another maker's plate, it is quoted from that plate through the heat exchanger pages.
Plates without the ZF prefix
A BW, HBW, HSW or IRM plate is read the same way as a ZF-prefixed one: type, serial and any build number stamped on it. When an item has been revised since the unit was built, the revision is named in the reply and the ship decides whether it suits its spares holding.
Thrusters and controls as separate lines
An AT or TT thruster, its upper gearbox clutch and its power pack are separate items from the main gearbox, and a control head belongs to its own system generation. Each is quoted on its own line, so one missing detail does not hold back the rest of the list.
ZF gearbox and thruster parts — questions from the engine room
Which data from a ZF type plate is needed for a gearbox parts enquiry?
The complete type with all suffix letters, the serial number and the parts list number are the core; the customer number, the ratio and the duty-class rating that applies help confirm the build. Add the oil type from the plate and whether a PTO, PTI or trolling valve is fitted. A clear photograph of the whole plate is better than a transcription.
Can single clutch plates be ordered for a ZF reverse-reduction gearbox?
They can be quoted, but the plates in one pack wear together, and the piston seals and sealing rings of the same pack are normally renewed at the same time. The parts list for the serial decides the plate count and execution, so plates are quoted per clutch pack against that list rather than by type name.
Our gearbox plate reads BW, HBW, HSW or IRM rather than ZF — is it covered?
Yes. ZF's current lubricant list TE-ML 04 covers the BW, HBW, HSW and IRM designations alongside the ZF-prefixed ranges, so these units are identified by type and serial in the same way. Send the plate photograph and the serial; if the plate is gone, photographs of the housing and of the removed part are the next step.
Which oil does ZF specify for its marine gearboxes and thrusters?
ZF publishes its own list of lubricants for marine transmissions and thrusters, TE-ML 04, which assigns lubricant classes to each product group and lists the trade products tested under each class; the operating instructions or the type plate give the change interval. One point matters on classed ships: for transmissions classified by DNV, ZF excludes the class that admits any engine oil meeting its specification and allows only the trade products listed under its classes 04B or 04C.
Can Vessel Core quote parts for ZF azimuth and tunnel thrusters?
Yes, against the thruster's own plate: the AT or TT designation with its variant letters, FP or CP execution, L- or Z-drive, the prime mover and the serial number. Propeller and steering pipe seal kits, upper gearbox clutch parts on diesel-driven units and CP power pack items are the usual lines. ZF's tunnel thruster documentation refers application questions to the technical staff of ZF Marine Krimpen in the Netherlands, and each item is checked against the serial and the unit's own parts book.
Is Vessel Core connected to ZF?
No, and there is no agreement of any kind. Vessel Core holds no distribution, representation or partnership agreement with ZF, and quoting a component against one of its designations implies no approval by the maker and no claim of interchangeability.
Send the whole type plate and the removed parts.
List the type with its suffix letters, the serial and parts list number, the items needed and the port. Clutch parts, cooler items and thruster or control lines are then quoted separately, so the ship can choose what to renew now and what to carry as a spare.
