TL-311J Flail Mower Gearbox Ratio 1:3 Replacement for Comer TL-311J Gearbox

Vegetation Shredding & Pasture Maintenance

This flail mower gearbox for sale powers the flail drum to cut and mulch grass, weeds, and crop residues across grazing pastures and hay meadows. The 1:3 ratio produces enough blade-tip speed for a fine mulch that breaks down quickly and returns nutrients to the soil. Regular pasture topping with a properly geared flail mower keeps weed seed heads from maturing and promotes even regrowth of desirable forage species over the following weeks.

Brush & Bramble Control

High-torque gearbox configurations in the TL-311 series handle tougher loads when shredding woody stems, blackberry canes, and dense vegetation along fence lines and field boundaries. The 210 Nm output torque lets the flail rotor chew through material up to about 30 mm in diameter without stalling. Operators who regularly clear neglected paddock edges or overgrown ditches rely on this gearbox to push through heavy material that would bog down lighter units.

Vineyard & Orchard Under-Row Work

Compact gearbox layouts suit the narrow-row flail mowers used between vine rows, citrus trees, and olive groves. Because the TL-311J shares the same housing envelope as the original Comer unit, it fits into tight offset mower frames without fouling on canopy supports or irrigation lines. Vineyard managers depend on the consistent rotor speed this 3 point flail mower gearbox delivers to keep inter-row growth short without throwing debris into the fruit zone.

Roadside & Municipal Mowing

Municipal crews and highway maintenance contractors need flail mower gearbox parts that survive frequent impacts from cans, bottles, stones, and miscellaneous road debris. The GGG40 ductile iron housing on the TL-311J absorbs these shock loads far better than cast aluminum alternatives. Verge mowing operations run for hundreds of hours each season, and this gearbox's 500-hour oil change interval keeps scheduled downtime to a minimum during the busiest cutting months.

Beheer van gewasresten

After harvest, the flail mower gearbox assembly drives the rotor that shreds corn stalks, soybean stubble, and cereal straw into a uniform mulch layer. Chopping residues speeds decomposition, reduces slug and pest habitat, and improves seed-to-soil contact for the following planting pass. The 36.8 kW input capacity of this gearbox handles the high continuous loads that long hours of post-harvest residue work demand on large arable farms.

Slope & Embankment Mowing

Arm-mounted flail heads used on excavator-based mowing rigs and steep-slope tractors require a gearbox that performs reliably at varying angles and under fluctuating gravitational loads on the oil sump. The splash-lubrication system inside the TL-311J keeps all internal surfaces coated even when the mower head tilts on steep banks. This makes it a practical choice for levee maintenance, canal bank mowing, and hillside pasture care where the working angle changes continuously.

Sports Turf & Amenity Grounds

Groundskeepers maintaining sports fields, parks, and golf course roughs use flail mowers for their ability to leave a clean, even finish without windrows. The precise 1:3 ratio in this flail mower right angle gearbox ensures consistent blade-tip speed across the full working width of the rotor, which translates directly into a uniform cut height. For amenity applications, the fine mulch the flails produce disappears into the turf canopy within a day or two, keeping the appearance neat.

Land Reclamation & Site Clearing

Before new construction, reforestation, or re-seeding projects begin, contractors use heavy duty flail mower gearbox configurations to clear overgrown ground quickly. The TL-311J transmits enough power to handle thick scrub, small saplings, and accumulated thatch on abandoned agricultural land. Once the site is cleared, the same machine can be used for ongoing maintenance, making the gearbox a long-term investment rather than a single-project consumable.

TL-311J Flail Mower Gearbox Components

Huisvesting
The housing is the structural shell of the flail mower gear box, cast from GGG40 ductile iron to provide high impact strength and vibration damping. It supports the internal shaft bearings, locates the gear mesh at the correct center distance, and shields every moving part from field debris. Precision-machined mounting faces on the housing accept standard bolt patterns so the gearbox attaches directly to the mower frame without modification.

Ingaande as
The input shaft transfers rotational energy from the tractor's PTO drive shaft into the gearbox gear set. On the TL-311J, it carries a 1"3/8 Z-6 spline that matches common agricultural PTO standards. The shaft is case-hardened to resist surface wear from repeated coupling cycles, and it runs on tapered roller bearings that handle both radial loads and the axial thrust generated by the helical tooth contact of the meshing gears.

Tandwielen
The gear set converts high-speed, lower-torque PTO input into the faster output rotation the flail rotor requires. This TL-311J uses a 23/24 tooth spur gear arrangement that provides the 1:3 speed increase. Both gears are forged from alloy steel and undergo carburizing heat treatment to harden the tooth surfaces while keeping the core tough enough to absorb sudden shock loads from obstructions encountered during mowing operations in the field.

Lagers
Tapered roller bearings support the input and output shafts, absorbing radial, axial, and combined loads while minimizing rotational friction. These flail mower gearbox bearings are selected for their load rating relative to the torque and speed this gearbox transmits, and they are installed with a controlled preload that eliminates shaft end-play. Proper preload keeps the gear mesh aligned, reduces noise, and prevents the uneven tooth contact that accelerates pitting and spalling.

Uitgaande as
The output shaft drives the flail mower's cutting rotor at the increased speed determined by the gear ratio. On the TL-311J, this shaft extends through the extension tube and connects to the drum via a keyed or splined coupling. Output shaft lengths range from approximately 500 mm to 1350 mm across different TL-311D extension configurations (Comer codes 9.312.505 through 9.312.507), allowing the gearbox to serve a wide variety of mower frame widths.

Oliekeerringen
The flail mower gearbox oil seal at each shaft opening prevents SAE 80W-90 gear oil from leaking out and stops dirt, water, and plant fibers from entering the gear cavity. These seals use a double-lip design with a spring-loaded primary lip that rides against a polished journal surface on the shaft. A secondary dust lip faces outward to deflect coarse particles. Seal failure is the most common cause of flail mower gearbox oil loss, making periodic seal inspection a priority maintenance task.

Breather Valve
Mounted on the top of the housing, the breather valve equalizes pressure between the gearbox interior and the atmosphere. As the gears rotate and generate heat, air inside the housing expands. Without a breather, that rising pressure would force oil past the shaft seals, causing leaks and creating a mess around the mower's cutting head. The valve contains a filter element that allows air to pass freely while trapping fine dust particles that could contaminate the oil.

Maintenance Instruction

1. Regular Oil Level Checks
Check the flail mower gearbox oil level and condition every 50 operating hours or before each week of steady use, whichever comes first. Remove the level plug on the side of the housing; oil should be visible at the plug opening or just below it. If the oil appears milky, it has absorbed moisture and should be drained and replaced immediately. Dark, gritty oil points to internal contamination from worn seals or a blocked breather, and both issues should be investigated before continuing work.

2. Seal & Fastener Inspection
Inspect the shaft seals, keyway fixings, and flail/knife mounting bolts before each cutting season or after extended heavy use. Oil stains around the input or output shaft indicate a worn or damaged flail mower gearbox oil seal that should be replaced before dirt enters the gear cavity. At the same time, check that all housing bolts are tightened to specification and that there is no visible cracking around the mounting flange or the extension tube joint, especially if the mower has struck a solid obstruction recently.

3. First Oil Change (Break-In Period)
During the initial break-in period of a new gearbox, typically the first 50 to 70 operating hours, gear teeth and bearing surfaces shed microscopic metal particles as they wear into each other. Drain the gearbox completely after this period, flush the housing with a small quantity of clean 80W-90 oil, and refill with fresh SAE 80W-90 gear oil to the correct level. Examining the drained oil on a magnetic drain plug gives you a baseline reading of normal break-in debris versus abnormal wear.

4. Scheduled Oil Changes
After the break-in drain, change the oil every 500 operating hours or at least once per year, whichever comes first. For continuous-duty operations that run the mower for long stretches, such as roadside maintenance contracts, consider shortening the interval to 300 hours. Always refill with SAE 80W-90 EP (extreme pressure) gear oil rated GL-4 or GL-5, and fill to the level plug opening. Running the gearbox on contaminated or degraded oil accelerates gear tooth pitting and shortens bearing life significantly.

5. Post-Overload Inspection
Replace shear bolts or reset the slip clutch after any overload incident, such as striking a large rock, fence post, or buried concrete slab. After resetting the safety device, drain a small oil sample from the gearbox and inspect it for unusual metal particles or discoloration that might indicate internal damage. Record each overload event in your maintenance log to detect recurring issues that may point to a field hazard or an operating practice that is putting excessive strain on the driveline.

6. Verify Compatibility Before Ordering
Before ordering a flail mower gearbox replacement, verify the PTO speed and type (540 or 1000 RPM), input and output shaft diameters, keyway specifications, mounting bolt pattern, and the required gear ratio. The TL-311J covers 540 RPM applications with a 1:3 ratio and 1"3/8 Z-6 spline connections. If your mower requires a different extension length or shaft end type, check the full TL-311 series catalog or contact CMN Transmission for cross-reference assistance against your current Comer part number.

7. External Cleaning & Breather Care
After each mowing session, clean accumulated grass, mud, and debris from the outside of the gearbox housing, paying close attention to the area around the breather valve, seals, and drain plug. A clogged breather traps expanding air inside the housing, which pushes oil past seals and creates leaks. Remove the breather cap periodically and blow it out with compressed air or soak it in solvent to dissolve caked grass residue. Keep the housing exterior clean so that fresh oil leaks are easy to spot during your next walk-around inspection.

8. Voorbereiding voor seizoensgebonden opslag
Before putting the mower into off-season storage, top up the gearbox oil to the fill plug level. A full oil charge minimizes the amount of air and moisture inside the housing, which reduces condensation that can corrode gear teeth and bearing surfaces over winter. Rotate the input shaft by hand a few times to coat all internal surfaces with fresh oil. Apply a thin film of grease or anti-corrosion spray to the exposed portions of the input and output shafts, and store the machine in a dry, covered area to protect the gearbox from direct weather exposure.

Flail Mower Gearbox and PTO Drive Shaft

The flail mower gearbox and the PTO drive shaft work as a paired system that moves rotational power from the tractor to the cutting rotor. A PTO drive shaft for a flail mower is a mechanical driveline that transfers rotational power from the tractor's PTO stub shaft to the mower gearbox input. It typically consists of a telescoping tubular shaft, two universal joints (also called cross joints or U-joints), a splined slip joint that accommodates length changes as the implement follows the ground contour, and a plastic or metal safety shield that covers the spinning shaft. The shaft's spline on the tractor end matches the PTO stub (commonly 1"3/8 Z-6 for 540 RPM systems), and the implement end carries a matching yoke that slides onto the gearbox input shaft spline.

The connection between the PTO shaft and the TL-311J gearbox is made through the 1"3/8 Z-6 splined input shaft. The yoke on the implement end of the PTO shaft slides over this spline, and a locking collar or shear pin secures the coupling. Proper shaft sizing is critical: the PTO shaft must be rated for at least the same torque and speed as the gearbox input (36.8 kW at 540 RPM in this case). Undersized shafts will fail at the universal joints or twist the telescoping tubes, while oversized shafts add unnecessary weight and cost. The operating angle between the tractor PTO and the gearbox input should be kept below 25 degrees to avoid premature U-joint wear, and both U-joints should operate at roughly equal angles to cancel out speed fluctuations.

Bij het selecteren van een PTO-as for use with the TL-311J flail mower PTO gearbox, verify that the shaft's torque rating exceeds the gearbox's maximum input power, that both yoke bore sizes match the tractor's PTO stub and the gearbox input shaft, and that the collapsed and extended lengths fit your tractor-to-mower geometry. Shafts with wide-angle U-joints are recommended for three-point-hitch mounted mowers that experience large angular changes during transport and headland turns. Lubricate the U-joints and the slip joint according to the shaft manufacturer's schedule, which is typically every 8 to 10 operating hours. A seized U-joint or a dry slip joint will transmit vibration into the gearbox and accelerate bearing wear, so this simple greasing routine protects both the shaft and the gearbox investment.

Always ensure the PTO safety shield is in place and rotates freely before starting the mower. A jammed shield can overheat and melt, and an unshielded spinning shaft is a serious entanglement hazard. If the shield is damaged, replace it before operating the machine. The shaft and gearbox together form the complete power path from tractor to flail rotor, and both must be in serviceable condition to deliver safe, reliable performance.

Flail Mower Gearbox vs. Rotary Cutter Gearbox

Wat is een versnellingsbak voor een klepelmaaier?

Flail mower gearboxes are critical power-transmission components in agricultural and municipal machinery. They receive rotational energy from the tractor's PTO or engine and deliver it to the flail rotor at the correct speed and torque for consistent cutting performance. Internal gear systems regulate the speed ratio to match different crop types, residue thicknesses, and terrain conditions, while heavy-duty housing materials and hardened gear teeth provide long-term mechanical reliability under demanding field conditions.

Voordelen van een versnellingsbak voor klepelmaaiers

• Fine Mulch Output: The speed-increasing ratio produces high blade-tip velocity that shreds material into small particles, which decompose faster than coarse clippings left by rotary cutters and return nutrients to the soil more quickly.
• Reduced Projectile Risk: Flail blades swing on pivoting mounts rather than spinning as rigid bars, so when they strike a stone or other hard object, they retract rather than launching debris at high velocity, making flail mowers safer for roadside and public-area work.
• Even Finish Quality: The flail drum design with multiple small blades running close to the ground produces a uniform cut without the streaking or windrow effect that single-blade rotary cutters sometimes leave behind.
• Versatility in Terrain: Flail mower gearboxes work effectively on slopes, undulating ground, and rough pastures where a rigid rotary cutter would scalp high spots and miss low spots.

Toepassingen van de versnellingsbak van de klepelmaaier

• Pasture maintenance and hayfield topping across dairy, beef, and sheep operations where fine mulch and even regrowth are priorities.
• Roadside verge and highway median mowing where safety regulations restrict projectile risk in the vicinity of traffic and pedestrians.
• Vineyard and orchard inter-row management where compact mower heads need controlled vegetation removal without damaging trunks or irrigation lines.
• Post-harvest residue chopping on arable farms to accelerate decomposition and prepare fields for the next planting cycle.

Wat is een tandwielkast voor een roterende snijder?

A rotary cutter gearbox is an essential power-transmission component in rotary cutters (also called bush hogs or slashers), which are commonly used for mowing tall grasses, heavy weeds, and light brush. These gearboxes are designed to withstand the high torque and sudden shock loads encountered when thick vegetation or hidden debris wraps around or strikes the large, rigid cutting blades. The gearbox consists of precisely engineered gears, typically in a 1:1 or low-ratio reduction configuration, that transfer PTO power through the input shaft and down to the horizontal cutting blades via the output shaft. The input shaft connects to the tractor PTO spline, and the vertical output shaft turns the blade carrier below the cutter deck.

Voordelen van een tandwielkast voor roterende maaiers

• Hoge koppelafgifte: Rotary cutter gearboxes transmit maximum torque at lower blade speeds, giving the cutting blades enough force to shear through thick brush, small saplings, and heavy weed patches.
• Simple Blade System: Two or three large free-swinging blades are easier and cheaper to replace than a full set of flail knives, which can reduce maintenance costs on operations that frequently damage blades on rocky ground.
• Wider Cutting Swath: Rotary cutters are available in very wide single-deck and multi-deck configurations that cover large areas quickly, making them cost-effective for broad-acre clearing and rough mowing.
• Tolerantie voor schokbelasting: Built with shear-bolt or slip-clutch protection and vertical output shafts rated for high bending loads, rotary cutter gearboxes are engineered to survive repeated impacts from rocks and stumps.

Toepassingen van de tandwielkast van de roterende snijder

• Grass cutting and residue shredding on rough pastures and CRP land where finish quality is less important than speed and coverage.
• Brush and woody-stem clearing on fence lines, pipeline corridors, and overgrown field corners where heavy material would overload a flail head.
• Stubble management and field preparation after grain harvest, where the goal is to chop standing stalks before tillage rather than produce a fine mulch.
• Orchard and vineyard alley work in operations that prefer low-profile cutter decks, though flail mowers are generally more popular for close inter-row work.

Vergelijkingstabel

Functie	Versnellingsbak van de klepelmaaier	Tandwielkast van de roterende snijder
Typische verhouding	1:3 speed increasing	1:1 or low reduction
Uitgangssnelheid	High (1500+ RPM)	Low to Medium (300-540 RPM)
Output Orientation	Horizontal (to rotor)	Vertical (downward to blades)
Snijkwaliteit	Fine mulch, even finish	Coarse cut, windrows possible
Projectile Risk	Low (pivoting flails)	Higher (rigid blades)
Best for Brush	Light to moderate	Moderate to heavy
Terreinaanpassingsvermogen	Excellent (follows contour)	Moderate (rigid deck)
Blade Replacement Cost	Higher (many small blades)	Lower (2-3 large blades)
Typisch gebruik	Pastures, roadsides, orchards	Rough clearing, field edges

Why Choose CMN Transmission's Flail Mower Gearboxes?

Korea CMN Transmission Co., Ltd. was established in 2000 and operates from its manufacturing facility at Sandan-o, Danwon-gu, Ansan-si, Gyeonggi-do, Korea. With more than 100 factory employees, CMN Transmission focuses exclusively on the research, development, manufacturing, sales, and after-sales service of agricultural gearboxes and related power-transmission components. Over the past two decades, the company has built a reputation as a dependable supplier in the global agricultural gearbox market, now exporting to more than 60 countries across six continents.

The product range covers rotary cutter gearboxes, rotary tiller gearboxes, feed mixer gearboxes, rotary mower gearboxes, fertilizer spreader gearboxes, flail mower gearboxes, post hole digger gearboxes, round baler gearboxes, square baler gearboxes, disc mower gearboxes, center pivot irrigation gearboxes, hydraulic drive gearboxes, silage machine gearboxes, orchard sprayer gearboxes, rotary rake gearboxes, combine harvester gearboxes, grain storage gearboxes, grain transportation gearboxes, corn headers gearboxes, cutting bar gearboxes, poultry feeding gearboxes, and custom agricultural gearbox solutions covering nearly one thousand unique specifications. Alongside gearboxes, CMN supplies PTO shafts, U-joints, yokes, tubes, torque limiters, covers, adapters, couplings, bearings, blades, chains, and sprockets for a full driveline solution.

Annual production exceeds 500,000 units, and every product is manufactured under CE and ISO 9001 certified quality management systems that control raw material sourcing, machining tolerances, heat treatment, assembly, and final testing. Each gearbox undergoes a run-in test and a leak-down check before it leaves the factory floor. This level of process control is what allows CMN Transmission to offer flail mower gearbox replacements that match OEM specifications at a competitive price point.

When you purchase an agricultural flail mower gearbox from CMN Transmission, you benefit from direct factory pricing without intermediary markups, a technical support team that can cross-reference your existing Comer, Omni Gear, or other OEM part number to the correct CMN model, and a global logistics network that delivers to North America, South America, Europe, the Middle East, Southeast Asia, and Oceania. Products are exported regularly to the United States, Canada, Mexico, Brazil, Argentina, France, Germany, Italy, Spain, the United Kingdom, Russia, China, India, Thailand, Vietnam, Turkey, Australia, and New Zealand.

CMN Transmission supports custom production based on customer drawings and specifications for agricultural gearboxes, PTO shafts, and various agricultural machinery components. Whether you need a single replacement unit or a container load of gearboxes for OEM assembly lines, the CMN team has the engineering capability and manufacturing capacity to deliver. Contact us for a quote on the TL-311J or any other flail mower gearbox in our catalog.

Veelgestelde vragen

Q: What oil should I use in a flail mower gearbox?
A: The TL-311J requires SAE 80W-90 gear oil rated GL-4 or GL-5. This viscosity grade provides the right balance of film thickness and flow at the operating temperatures a flail mower gearbox typically reaches during field work. Fill the gearbox to the level plug opening, which corresponds to the full 1.2 L capacity. Avoid using engine oil, hydraulic fluid, or multi-purpose grease as a substitute, because these lubricants do not have the extreme-pressure additives that protect hardened gear teeth under high contact loads.

Q: Is the TL-311J a direct replacement for Comer TL-311J flail mower gearbox?
A: Yes. This gearbox is manufactured to match all critical dimensions of the original Comer TL-311J (code 311.8) and TL-311A (code 311), including the mounting bolt pattern, shaft centerlines, input/output spline profiles, and housing envelope dimensions. You can swap the CMN unit into your existing mower frame without modifications. All Comer 9.311.xxx variant codes, including different extension lengths and free-wheel options, are covered across the TL-311 product family.

Q: How often should I change the oil in my flail mower gearbox?
A: Perform the first oil change after 50 to 70 operating hours to flush out break-in debris. After that, change the oil every 500 operating hours or at least once a year, whichever milestone arrives first. If you run the mower in dusty, sandy, or extremely wet conditions, shorten the interval to 300 hours. Always inspect the drained oil and the magnetic drain plug for metal particles that could signal internal wear before refilling.

Q: What does the 1:3 flail mower gearbox ratio mean?
A: A 1:3 ratio means the output shaft rotates three times for every one revolution of the input shaft. This is a speed-increasing (multiplier) configuration. When connected to a standard 540 RPM PTO, the gearbox output reaches approximately 1620 RPM, which is within the typical operating range for flail mower rotors. The higher rotor speed provides the blade-tip velocity needed for a clean cut and fine mulch production.

Q: Can this gearbox be used on a 3 point flail mower?
A: Yes. The TL-311J is designed for tractor-mounted flail mowers, and the majority of these machines use a three-point hitch attachment. The gearbox accepts a standard 1"3/8 Z-6 PTO shaft input, which is the same connection used on virtually all 540 RPM three-point-hitch implements. Verify your mower's mounting bolt pattern and shaft configuration against the TL-311J specification sheet before ordering, or contact CMN Transmission with your mower make and model for a cross-reference.

Q: What are the common signs that a flail mower gearbox needs repair?
A: Watch for unusual noise (grinding, whining, or knocking), oil leaks around the shaft seals or housing joints, overheating during normal operation, reduced rotor speed or uneven cutting performance, and excessive play or looseness when you try to rock the output shaft by hand. Any of these symptoms warrants stopping the machine and inspecting the gearbox before the problem escalates into a more expensive failure. Catching bearing or gear wear early through regular flail mower gearbox repair inspections can save you the cost of a full replacement.

Q: Does the TL-311J gearbox come with oil pre-filled?
A: No. All CMN Transmission gearboxes ship dry (without oil). This is standard practice because it allows you to fill the unit with the exact oil brand and grade your maintenance program specifies, and it avoids the risk of leaks during shipping. Before operating the gearbox for the first time, fill it with 1.2 L of SAE 80W-90 gear oil through the fill plug until oil reaches the level plug opening.

Q: What is the maximum input power rating for this 540 RPM flail mower gearbox?
A: The TL-311J is rated for a maximum input power of 36.8 kW (approximately 50 HP) at 540 RPM. If your tractor can deliver more than 50 HP to the PTO, the gearbox will still function correctly as long as the mowing load does not continuously exceed the 36.8 kW limit. For higher-power applications or sustained heavy-duty use above this threshold, consider the larger TL-312A gearbox from the CMN Transmission range, which handles up to 76.5 kW.

Q: Can I get replacement seals and bearings for the TL-311J?
A: Yes. CMN Transmission supplies individual flail mower gearbox parts including oil seals, bearings, gears, shafts, breather valves, and drain plugs for the TL-311J. If you only need to reseal the gearbox or replace worn bearings rather than buying a complete unit, contact the CMN sales team with your gearbox model and Comer code reference (e.g., 9.311.083) and they will supply the correct components for your specific configuration.

Q: Is this gearbox compatible with the replacement for Comer T-310A flail mower gearbox?
A: The TL-311J and the TL-310J/TL-310A are different models in the Comer flail mower range. The TL-310 series has a slightly smaller housing, lower power rating (22.1 kW), and different mounting dimensions. They are not directly interchangeable. If your mower uses a Comer T-310A, you need the corresponding CMN TL-310J replacement gearbox, not the TL-311J. Always verify the model number stamped on your existing gearbox housing before ordering.

Klantenrecensies

Tom Hartley, Arable & Livestock Farming, United Kingdom
"We run three Kuhn BV flail mowers on our 1,200-acre mixed farm in East Anglia and go through a gearbox every few years because of the flint in our soil. Ordered a TL-311J as a Comer replacement last spring. Mounting holes lined up exactly, the 1"3/8 Z-6 spline was a clean fit on our PTO shaft, and the first oil change at 60 hours came out looking normal. We have about 280 hours on it now and it still runs quietly. Paid noticeably less than the dealer-sourced Comer unit. Happy with the purchase."

Klaus Berger, Municipal Road Maintenance, Germany
"Our municipal works department maintains about 180 km of roadsides in rural Bavaria, and we need gearboxes that hold up to rocks and debris all season long. The CMN TL-311J has been running on our Mulag mower since April with zero leaks and no unusual noise after roughly 400 hours. The cast iron housing feels solid and the oil was still clean at the 300-hour check. Delivery took about three weeks to southern Germany, which was acceptable. We will order a second unit for the backup machine."

Mark Sullivan, Viticulture, Australia
"I manage a 50-hectare vineyard in the Barossa Valley and our under-row Berti flail mower needed a new gearbox after the original Comer unit started leaking oil from the output seal. The TL-311J dropped right into the same mounting bracket. The 1:3 ratio gives us the rotor speed we need to keep the inter-row growth short without throwing stones into the vine canopy. My only minor complaint is that the gearbox arrived without clear English instructions for the break-in oil change interval, but I found the information online easily enough."

Darren Foss, Cattle Ranching, Canada
"We bought two TL-311J gearboxes for our pasture maintenance operation in southern Alberta. Both are mounted on Schulte FX-520 flail mowers behind 80 HP tractors. After a full season of mowing alfalfa regrowth and volunteer canola, roughly 350 hours per unit, neither gearbox has given us any trouble. The weight is close to the original at 20.5 kg, so it did not affect the balance on the three-point hitch. Good value for a mid-size cattle operation trying to keep machinery costs under control."

Roberto Mello, Coffee Farming, Brazil
"Comprei a caixa de engrenagens TL-311J para substituir a Comer original no meu triturador Dragone. Purchased the TL-311J to replace the worn Comer on our Dragone flail mower used for coffee-field inter-row work in Minas Gerais. The spline dimensions were exactly right, 1"3/8 Z-6, and the gearbox runs smoothly at 540 RPM. I changed the oil at 65 hours and found only a small amount of normal break-in particles. The customer service team at CMN responded quickly when I asked about the correct extension tube length. Very satisfied."

Andrea Colombo, Pasture and Orchard Mowing, Italy
"We operate a contract mowing business in Lombardy and service about 200 hectares of pasture and orchard each month from March to October. Our Comer gearboxes were getting expensive to replace through Italian dealers, so we tried the CMN TL-311J this year. After 500 hours of hard use on our Falc Pegasus mower, the gearbox is performing exactly like the original. Oil stays clean between changes, no leaks, no noise. I appreciate that the gearbox ships without oil so I can fill it with the same Castrol Syntrax we use across our whole fleet."

Kevin Schafer, Dairy Farming, United States
"I run a small dairy operation with 120 acres of pasture in Wisconsin and needed an affordable gearbox for my Maschio Barbi flail mower. The old Comer unit had worn splines and was starting to whine under load. This TL-311J was roughly 40% less than the Comer quote from my local dealer. Installation took about 45 minutes. The gearbox has about 200 hours on it now and everything checks out fine at each weekly oil level inspection. Shipping to the US took about two and a half weeks, which I thought was reasonable for an overseas order."

Pierre Dumont, Municipal Works, France
"Nous utilisons le TL-311J sur notre broyeur Rousseau pour l'entretien des bords de routes communales. We use it on our Rousseau flail mower for communal roadside maintenance in the Loire Valley. After a full 450 hours of use this year, the gearbox still runs like new. The 210 Nm torque output handles the mixture of grass, brambles, and small branches we encounter along country roads without any problem. I was especially pleased with how quickly CMN processed the order and provided the tracking number. Will be recommending this to other communes in our department."

Martin Ruiz, Grain & Sugar Cane Farming, Argentina
"We farm sugar cane and soybeans on about 800 hectares near Tucuman and use flail mowers to manage cover crops and post-harvest residue. Bought three TL-311J units to replace Comer gearboxes on our Mainero flail heads. All three bolted in with no issues, the spline profile matched perfectly. We filled them with 80W-90 as recommended and did the first oil change at 55 hours. After a full harvest season, roughly 380 hours per unit, all three gearboxes are running well. The price-to-quality ratio is very competitive for the Argentine market."