Massey Ferguson 6445 Tractor Specs Review

Massey Ferguson 6445 Tractor Engine

Power at 2200 rpm, ISO hp (kW) – 90 (67)
Model – PERKINS 1104 C-44T
Number of cylinders/displacement – 4 / 4.4 Turbo
Injection pump – Lucas DP 210
Fan – Viscostatic
Alternator – 80 A

MF 6445 Tractor Gearbox

Gearbox model – GBA20 (4×4)
Clutch/shuttle – Power Shuttle
Type – Dynashift
AutoDrive – optional
Creeper unit 4/1 – optional
Creeper unit 14/1 – optional

Massey Ferguson 6445 Tractor Rear axle

Axle model – GPA20
Final drives – HD
Axle shaft D – 76 mm
Flanged shaft – standard
Brake discs per trumpet housing – 1
Hand brake discs – 3
Differential lock – Dog clutch


Stabilisers – telescopic
Multi-hole drawbar – optional
3-point linkage – Cat. 2, hook or ball type
Clevis hitch – Fast-setting or pin-adjusting scale
Automatic clevis hitch – Fast-setting or pin-adjusting scale
Semi-mounted trailer hitch – Stud or auto-hitch
Swinging drawbar – standard
Roller type swinging drawbar – optional

MF 6445 Tractor Power take-off

Type – Interchangeable / shiftable shaft
540/1000/eco – optional
750/1000 – optional
Number of clutch discs – 4
PTO brake – hydraulic
Proportional PTO – optional
Automated PTO – optional
Front power take-off – optional

Massey Ferguson 6445 Tractor Front

Model – AG 85
Type – fixed or suspended (optional)
Rotational direction – Clockwise
Number of clutch discs – 4
Swivelling mudguard (4WD) – optional
2-wheel drive – optional
Front linkage (optional) – 2.5 T

MF 6445 Tractor Hydraulic

Open Centre 57 l/min – optional
TFLS 100 l/min – optional
Closed Centre 110 l/min – optional
Orbitrol steering – 125 cc
Brake master cylinder – standard
Braking assistance – optional
Trailer brake – optional
Auxiliary spool valves (maximum number) – 4 electrohydraulic (2 SMS) or
4 mechanical
Couplers – Decompression


Transmission control – AUTOTRONIC 3
Instrument panel – DCC2
Linkage controller – EHRC
Draft sensors – 2
Sensor capacity – 4 T (standard) or 6 T (optional)
Datatronic – optional
Dual control (front and rear) – optional
TIC with/without draft sensor – optional
Fieldstar – optional


Suspension – optional
Rear-view mirrors – manual (standard) or electric (optional)
Air conditioning – manual (standard) or automatic (optional)
Standard bonnet – Fixed
Bonnet option – Hinged
Standard roof – standard
High-visibility roof – optional
Sloping bonnet – optional

Massey Ferguson 6445 Tractor Gearbox

The Dynashift unit is mounted between the reverse clutch of the power
shuttle and the mechanical unit consisting of the drive pinion. It is a
hydraulically operated gear shift mechanism which provides the MF 6445
tractor gearbox with four input ratios.

The function is ensured by two epicyclic gear trains linked to two
hydraulic clutches. Dynashift design enables selection of four ratios,
without declutching, using a lever located under the steering wheel.

The Dynashift unit is controlled by two solenoid valves mounted on the
clutch unit located on the front right-hand side of the gearbox. The two
solenoid valves are controlled by the electronic system of the Massey
Ferguson 6445 tractor.

The Dynashift input unit comprises two
epicyclic gear trains:

– the primary epicyclic gear train, the main part of the input unit,
used to transmit the movement from the engine to the gearbox,

– the secondary epicyclic gear train controls the speed of the primary
sun gear.

Primary epicyclic gear train

The movement enters via the primary ring gear which is splined onto the
transmission shaft. It rotates at engine speed.

The movement exits via the planet carrier which is splined onto the
secondary shaft.

The primary sun gear is driven by the secondary epicyclic gear train.

The speed of this sun gear determines the drive unit ratio of the MF6445 tractor gearbox.

Secondary epicyclic gear train

This epicyclic gear train is controlled by hydraulic clutches and

The secondary ring gear is:

– either locked on the primary shaft by three clutch discs and the
Belleville washer located in the front part of the unit,

– or immobilised in relation to the housing by three brake discs and a

When there is no pressure, the piston is pulled back by the twelve
springs and the Belleville washer by means of the thrust plate.

When the 17 bar pressure is built up in the circuit, the piston moves
forward and locks the brake discs while pushing the thrust plate that
compresses the Belleville washer.

The speed of the secondary ring gear is
established as follows:

– speed equals engine speed if the front piston is not under pressure,

– speed nil when the front piston is under pressure.

The secondary sun gear is either:

– locked on the secondary shaft with four clutch discs and a Belleville
washer located on the rear part of the unit,

– or immobilised in relation to the housing by means of three brake
discs and a piston.

When there is no pressure, the piston is pushed forward by the
Belleville washer and six springs. The 17 bar pressure moves the piston
back and locks the brake discs.

It compresses the Belleville washer by means of the thrust plate which
releases the clutch discs of the secondary shaft.

Immobilisation of either the secondary ring gear or the secondary sun
gear modifies the speed of the secondary planet carrier.

The latter drives the primary sun gear, and this establishes the gearbox
drive unit ratio.

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