GMD 51 TL Series


Trailed Simplicity and Versatility

With working widths ranging from 9’2” to 13’, KUHN GMD 51 TL Series mowers get you in and out of the field faster.

Contact your dealer for pricing

Find a dealer near you

As the first to market and industry leader, KUHN knows disc mowers. The GMD 51 TL Series trailed disc mowers have many of the same great features you have come to know and love. These trailed mowers offer high working rates, simple adjustments and low maintenance for dependable grass and forage harvesting. They provide easy tractor attachments, as well as improved contour following, compared to the fully mounted models. The trailed design also lowers the tractors ballast requirement, allowing use with smaller tractors while maintaining excellent stability in both work and transport.

Your benefits

The Optidisc® Elite Cutterbar: A Clean and Consistent Cut


Lubed-For-Life Optidisc® Elite Cutterbar

The Optidisc® Elite cutterbar provides a flat, streamlined profile so that soil and crop residue do not accumulate and material flows smoothly, even in heavy, difficult crop conditions. Optidisc Elite cutterbars are designed and tested with a zero oil change interval. The highly-polished gears and synthetic gear oil ensure that this system does not require any regular internal maintenance, eliminating the need for cutterbar oil changes throughout the life of the machine.

Differential Disc Spacing

The innovative design of the Optidisc Elite cutterbar offers exclusive differential disc spacing.
  1. Less Distance for a Clean Cut: Narrower spacing at diverging discs provides greater knife overlap, which results in a clean cut, even when the grass is short or light.
  2. More Distance for Easy Crop Passage: Wider spacing at converging discs provides more space for the crop to pass. Cut crop is quickly carried away from the cutting area, greatly improving the cut quality.

Discs & Open Cones

The new style discs incorporate flat angled leading edges to lift the crop off of the cutterbar and promote fast movement of the crop through the machine to be laid in an even swath. On the underside of the disc, there are welded-on scrapers. These scrapers keep the cutterbar clean of mud, dirt and debris when mowing in wet or dusty conditions.

Similar to the discs, the open cones have large area leading edges to evacuate the crop being cut and push the crop towards the center of the machine leaving a desirable edge to the swath. The open cone design also makes them easier to clean for less machine vibration and easier access to bolts on the disc whenever maintenance needs to be performed.

Protectadrive® Disc Bearing Stations

  • Protectadrive® Safety: Every minute saved during the hay season is precious. Ultimate protection, from the externally removable Protectadrive disc bearing stations, provides maximum reliability and quick service. In the event of an impact between a disc and an obstacle, the shaft holding the disc can shear just above the bearing. This is thanks to its carefully dimensioned shear groove. As a result, the gear teeth are protected.
  • Extra Rigidity Where it Counts: Disc bearing stations are attached by bolts that pass through the entire cutterbar. This is an exceptionally strong and secure attachment with no risk of mount being torn out of the cutterbar in case of shocks. The disc drive pinion is held precisely in place, all resulting in excellent reliability and reduced maintenance costs.
  • Gear-to-Gear Power Transmission: Gear-to-gear power transmission, a staple of all KUHN disc mowers, allows for maximum power to be transferred through all gears in the cutterbar. Unlike other gear cutterbars, equal sized gears throughout reduces torque on the gear teeth and leads to unsurpassed reliability and longevity.

Exceptional Terrain Following


Pro-Active Lift®

This maintenance-free system allows the machine to quickly adapt to abrupt changes in terrain or when an obstruction is encountered in the field. The cutting head is able to move up and back simultaneously, dissipating the force of any impact and providing space to clear the obstacle. This unique design reduces scalping to preserve crop stubble and helps protect the machine from potential damage. A slotted linkage on each side provide guidance for the header and eliminates the need to run the hydraulics in the float position.

Constant Float Suspension

The header is suspended on each side by a long, large-diameter spring that provides a constant range of flotation. The floating head lifts up and back, and can oscillate from side-to-side, to closely follow the ground contours and conform to irregular terrain. This reduces the amount of missed crop in the field and helps keep dirt out of the harvested crop.

Superior Maneuverability

The heavy-duty Gyrodine® gearbox is designed to withstand the most severe pull-through force from the hitch to the machine. The swivel design allows in excess of a 90° turn while keeping the PTO driveline straight. This design also allows extremely tight turns for clean, square corners while minimizing PTO vibration and wear.

Simple Design and Easy Service


Direct Drive Design

The direct design provides easy access for servicing and fully eliminates belts. Reliability is greatly improved when working in longer, tough or lodged crops. Unlike competitive models that require daily greasing, the driveshaft to the cutterbar uses maintenance-free U-joints. These joints reduce overall maintenance and eliminate excessive wear from improper maintenance.

Convenient Height Adjustment

The height change adjustments are fast and simple, and do not require tools. Cutting height is set using a special turnbuckle that adjusts easily with only modest effort. A convenient gauge on the turnbuckle shows the cutting height for precise field adjustments.

Steel Side Sheets

The steel side sheets provide a definitive line between cut and uncut crop. This makes the subsequent pass easier to follow for the operator and also gives the machine a finished look.

Toolless Hood Latch

Operators can easily open the front hood of the mower, with the pull of a lever, for clear access to the cutterbar for inspection or maintenance.




Working width
Transport width
Number of discs
Disc type
Blade retention system
Removable Protectadrive® disc bearing stations
Hydraulic lift mechanism
Cutterbar suspension
Safety guards
Cutting height
Suspension travel
Average swath width
Primary PTO
Secondary PTO shaft
PTO speed
Friction slip clutch
Minimum PTO power requirement
Required tractor hydraulic connections
Side sheets
Road lights and signaling
Machine weight approx.
GMD 2851 TLGMD 3151 TLGMD 3551 TLGMD 4051 TL
9'2" (2.8 m)10'2" (3.1 m)11'6" (3.5 m)13' (4.0 m)
9'4" (2.9 m)10'4" (3.2 m)11'8" (3.6 m)13'1" (4.0 m)
Optidisc® EliteOptidisc® EliteOptidisc® EliteOptidisc® Elite
Constant Float® suspension with Pro-Active Lift®Constant Float® suspension with Pro-Active Lift®Constant Float® suspension with Pro-Active Lift®Constant Float® suspension with Pro-Active Lift®
1.4" - 2.6" (35 - 65 mm)1.4" - 2.6" (35 - 65 mm)1.4" - 2.6" (35 - 65 mm)1.4" - 2.6" (35 - 65 mm)
+10" to -4" (+25.4 cm to -10.2 cm)+10" to -4" (+25.4 cm to -10.2 cm)+10" to -4" (+25.4 cm to -10.2 cm)+10" to -4" (+25.4 cm to -10.2 cm)
5'8" (1.8 m)7'3" (2.2 m)8'6" (2.6 m)10' (3.0 m)
Trailed, must choose drawbar or 2-point semi-mounted, Cat. 2 or 3N Quick hitch compatibleTrailed, must choose drawbar or 2-point semi-mounted, Cat. 2 or 3N Quick hitch compatibleTrailed, must choose drawbar or 2-point semi-mounted, Cat. 2 or 3N Quick hitch compatibleTrailed, must choose drawbar or 2-point semi-mounted, Cat. 2 or 3N Quick hitch compatible
9.5L - 159.5L - 159.5L - 159.5L - 15
1-3/8" - 6-spline1-3/8" - 6-spline1-3/8" - 6-spline1-3/8" - 6-spline
Friction slip clutch standardFriction slip clutch standardFriction slip clutch standardFriction slip clutch standard
540 (factory fitted) or 1,000 thru field kit conversion540 (factory fitted) or 1,000 thru field kit conversion540 (factory fitted) or 1,000 thru field kit conversion540 (factory fitted) or 1,000 thru field kit conversion
Standard with friction slip clutchStandard with friction slip clutchStandard with friction slip clutchStandard with friction slip clutch
40 hp (30 kW)47 hp (35 kW)54 hp (40 kW)60 hp (45 kW)
2 DA2 DA2 DA2 DA
2,520 lbs (1,143 kg)2,800 lbs (1,270 kg)2,920 lbs (1,324 kg)3,000 lbs (1,360 kg)


Available applications:GMD 51 TL Series

Logo KUHN ForageXpert

KUHN ForageXpert

For a powerful forage harvesting chain. This new application is available to help you find mowers, mower conditioners, tedders and rakes best adapted to your needs. It will help you optimize forage harvesting according to your current or future equipment purchases.
Download on the App Store

Check all our other KUHN apps to optimize your farm and your life

Get it on Google Play