What Is a Hay Tedder?
A hay tedder is a forage conditioning implement designed to accelerate the drying of cut hay. After a mower lays hay down in a swath, the tedder picks it up, flips it, and redistributes it loosely across the field — exposing more surface area to sun and airflow. The result is faster, more even drying, which translates directly into higher-quality hay with better color, leaf retention, and nutritional value.
In practical terms, a tedder can cut drying time by 30–50% compared to leaving hay undisturbed. In regions with unpredictable weather windows, that time savings is the difference between putting up quality hay and putting up a moldy mess.
Tedders are available in several configurations:
- Single rotor tedders — compact, ideal for smaller acreage and tight fields.
- Multi-rotor tedders — wider working widths for high-volume operations; rotors are typically arranged in a line or offset pattern.
- Trailed tedders — pulled behind the tractor on their own running gear, suited for very wide working widths.
- Mounted/3-point tedders — attached directly to the tractor's 3-point hitch, more maneuverable in smaller fields.
How a Hay Tedder Works
The core mechanism of a tedder is simple but effective. Each rotor consists of a central hub with multiple tine arms radiating outward. Each tine arm carries two or more curved tines. As the PTO drives the rotors at high speed (typically 540 RPM), the tines sweep through the hay swath, lifting and throwing the material in a wide, airy pattern behind the machine.
On multi-rotor tedders, adjacent rotors counter-rotate, working together to move hay across the full working width without leaving gaps or bunching. The working height is controlled by gauge wheels or skid shoes, which keep the tines at the correct distance from the ground — close enough to pick up all the hay, but not so low that they dig into the soil and contaminate the windrow.
The key to effective tedding is timing and conditions. Tedding works best when the hay has wilted slightly after cutting (typically 2–4 hours after mowing) and when conditions are sunny and breezy. Tedding wet hay too aggressively or too late in the drying process can cause leaf shatter and dry matter loss — especially in legumes like alfalfa and clover.
Wear Parts on a Hay Tedder
Tedders are mechanically straightforward, but they operate at high speed in abrasive conditions. The following components are the most frequently worn or damaged and should be inspected regularly and stocked as spares.
1. Tines
Tines are the highest-wear item on any tedder — bar none. They are the only part of the machine in direct, continuous contact with the crop and, frequently, the ground.
What they do: Curved spring-steel tines attach to the tine arms and do the actual work of lifting and throwing the hay. Their curved profile and spring temper allow them to flex on impact and return to shape.
How they wear: Tines wear at the tip from abrasion against soil and crop material. They also fatigue and crack at the bend point from repeated flexing, especially if the tedder is run too low or in rocky conditions. A tine that has lost tip length becomes less effective at picking up hay cleanly.
Signs of wear: Shortened or blunted tips, visible cracks at the bend, tines that no longer return to their original shape after flexing, or tines that have broken off entirely.
Replacement interval: Inspect every season; replace when tips are visibly worn or any cracking is present. Always replace in complete sets per rotor arm to maintain balance.
Stocking recommendation: Keep at least one full set of tines per rotor on hand. Tines are inexpensive individually — running out mid-season is not.
2. Tine Holders / Tine Clips
Tines attach to the tine arms via holders or clips — typically a bolt-and-clamp or snap-in retainer system depending on the manufacturer.
How they wear: Holders loosen over time from vibration, and the clamping surfaces wear, reducing their ability to hold the tine securely. A loose tine holder allows the tine to shift position, reducing effectiveness and accelerating tine wear.
Signs of wear: Tines that rotate or shift position during operation, visible wear on the clamping faces, holders that won't torque to spec.
Replacement interval: Inspect at every tine replacement. Replace any holder that shows wear or won't hold torque.
3. Tine Arms
Tine arms are the radial arms that extend from the rotor hub and carry the tines. They are typically made from formed steel or cast iron depending on the design.
How they wear: Tine arms bend or crack from rock strikes or from operating with a seized or missing tine that throws the rotor out of balance. On some designs, the tine arm pivot point wears, allowing excessive play.
Signs of wear: Visible bends or cracks, arms that are not parallel to adjacent arms, excessive play at the pivot point.
Replacement interval: Replace immediately upon discovery of any bend or crack. A broken tine arm at operating speed can cause significant secondary damage.
4. Rotor Bearings
Each rotor spins on one or more bearings housed in the rotor hub. These bearings carry the full radial and axial load of the spinning rotor and its tines.
How they wear: Bearings wear from inadequate lubrication, contamination (dust, crop debris, moisture), and normal fatigue over time. High-speed operation makes contamination especially damaging — even small amounts of grit in a bearing running at 540 RPM cause rapid wear.
Signs of wear: Rumbling, grinding, or squealing from the rotor hub. Excessive heat at the hub after operation. Visible wobble or play in the rotor. In advanced cases, the rotor may seize entirely.
Replacement interval: Inspect at the start of each season by spinning each rotor by hand and feeling for roughness or play. Replace at the first sign of roughness — a failed rotor bearing mid-season can destroy the hub and rotor shaft.
Lubrication: Grease all rotor bearing zerks daily during the season. Use the grease type and quantity specified by the manufacturer.
5. Gearbox
The gearbox transfers PTO power from the driveline to the rotor(s). On multi-rotor tedders, a central gearbox distributes drive to individual rotor gearboxes via driveshafts.
How it wears: Gearbox failures on tedders are almost always caused by oil starvation (low level, leaking seals, or operating on steep slopes), contamination from failed seals, or shock loads from rock strikes transmitted through the driveline.
Signs of wear: Gearbox overheating, whining or grinding noise, oil leaks at seals or the drain plug, metal particles visible when draining oil.
Maintenance: Check gearbox oil level at the start of each season and every 50 hours during use. Drain and replace oil annually. Inspect all seals for leaking.
Stocking recommendation: Keep the correct gearbox oil on hand and know your seal part numbers. Catching a leaking seal early is a $20 fix; ignoring it is a $500+ gearbox replacement.
6. PTO Driveshaft and Slip Clutch
The PTO driveshaft connects the tractor to the tedder gearbox. Most tedder driveshafts include a slip clutch to protect the driveline from shock loads.
How they wear: U-joints wear from inadequate lubrication and excessive operating angles. The telescoping section wears and can seize if not lubricated. The slip clutch wears from normal slipping events and can seize during off-season storage.
Signs of wear: Vibration or shudder in the driveline, clicking at low speed (worn U-joints), driveshaft that won't telescope smoothly, slip clutch that slips under normal load or won't slip at all.
Maintenance: Grease U-joints and the telescoping section at the start of each season. Exercise the slip clutch before first use by engaging and disengaging the PTO several times. Inspect the PTO shield for cracks or missing sections — replace immediately if damaged.
7. Gauge Wheels and Skid Shoes
Gauge wheels or skid shoes control the working height of the tedder — keeping the tines at the correct distance from the ground.
How they wear: Gauge wheel tires wear from ground contact, especially in abrasive or rocky soils. Skid shoes wear on their contact face and can wear through entirely if the tedder is operated too low or in stony conditions. Worn gauge wheels or skid shoes result in inconsistent tine height, leading to soil contamination in the hay or incomplete pickup.
Signs of wear: Visible wear on the skid shoe contact face, gauge wheel tires that are cracked, flat-spotted, or worn through, inconsistent tine height across the working width.
Replacement interval: Inspect at the start of each season. Skid shoes are sacrificial wear items — replace before they wear through to the frame.
8. Rotor Drive Chains or Belts (Where Applicable)
Some tedder designs use chains or belts to transfer drive between rotors or from the gearbox to the rotor. These are less common on modern designs but still present on many older machines.
How they wear: Chains stretch and wear at the pin and roller interfaces. Belts crack, fray, and lose tension over time. A worn chain or belt slips under load, reducing rotor speed and tedding effectiveness.
Signs of wear: Visible chain stretch (measure against a new chain), cracked or frayed belts, slipping or inconsistent rotor speed during operation.
Replacement interval: Measure chain stretch at the start of each season. Replace belts showing any cracking or fraying.
Pre-Season Tedder Inspection Checklist
Before the first cutting of the season, work through this inspection:
- Inspect every tine — replace any that are worn, cracked, or missing.
- Check all tine holders and clips for wear and proper torque.
- Spin each rotor by hand — feel for roughness or play in the bearings.
- Grease all zerks — rotor bearings, U-joints, pivot points, and gauge wheel hubs.
- Check gearbox oil level on all gearboxes. Look for leaks at seals and drain plugs.
- Inspect the PTO driveshaft — U-joints, telescoping section, slip clutch, and shields.
- Check gauge wheels and skid shoes for wear.
- Inspect the frame for cracked welds, especially at rotor mounts and hitch points.
- Check all hydraulic hoses and fittings for leaks or chafing (on folding models).
- Verify all transport locks and fold latches operate correctly.
Parts to Keep on Hand
Tedder downtime during haying season is costly. These are the parts worth stocking before the season starts:
- A full set of tines per rotor (minimum)
- Tine holders/clips
- Rotor bearings (at least one set)
- U-joint crosses for the PTO driveshaft
- Correct gearbox oil and seal kit
- Skid shoes or gauge wheel tires
Knowing your make and model before you need parts is half the battle. Having them on the shelf when something breaks is the other half.
Quality Farm Supply stocks tedder tines, bearings, gearbox components, driveline parts, and skid shoes for a wide range of tedder makes and models. Contact our team to find the right parts for your machine before the season starts.
