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PTO Extender Adaptor Female 21 Male 6 1 3 8 Spline for 70HP Engine
$87.79
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$87.79
Regular price
Available to Order
This PTO Extender Adaptor is a driveline extension coupler that adapts female 1-3/8" 21-spline to male 1-3/8" 6-spline PTO connections, made for 70HP-rated engines and standard Category 1 PTO drivelines.
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Product Overview
The PTO Extender Adaptor lengthens the reach of your power take-off shaft while converting spline configurations. It is built for owners of compact tractors, utility vehicles, and stationary engines using 1-3/8" PTO drives who need to bridge male 6-spline stubs to female 21-spline implements. This PTO Extender Adaptor ensures a secure, balanced coupling up to 70 horsepower.
Key Features & Performance
- Adapts male 1-3/8" 6-spline PTO stub to female 1-3/8" 21-spline implement shaft
- Extends overall PTO driveline length for added clearance and easier hookup
- Rated for engines up to 70 HP — handles demanding rotary cutter and tiller loads
- Precision-machined splines provide snug, low-vibration power transfer
- Heavy-duty steel construction with corrosion-resistant finish for long life
Fitment & Compatibility
- Fits standard 1-3/8" 6-spline male PTO shafts (common on older tractors)
- Accepts 1-3/8" 21-spline female implement yokes (many modern attachments)
- Designed for 70HP and under engines used in Category 1 PTO applications
- Compatible with tractors, gearboxes, and stationary power units using this spline standard
Common Uses
- Extending PTO length on rotary mowers, finish mowers, and flail mowers
- Adapting 6-spline tractor PTO to 21-spline equipment like post hole diggers and tillers
- Bridging short-coupled drivelines on backhoes, wood chippers, and generators
- Connecting stationary 70HP engines to PTO-driven pumps and compressors
Technical Specifications
- Input Connection: Female, 1-3/8 inch diameter, 21-spline
- Output Connection: Male, 1-3/8 inch diameter, 6-spline
- Maximum Horsepower: 70 HP
- PTO Series: 1-3/8 inch standard (Category 1)
Frequently Asked Questions
Q: Can I use this adaptor to connect a 6-spline tractor to a 21-spline implement? A: Yes, the adaptor’s female 21-spline side attaches to the implement yoke and its male 6-spline side slides onto your tractor PTO stub, provided both are 1-3/8" diameter.
Q: Will this work for implements that require a longer shaft? A: Absolutely, it extends the driveline by the adaptor’s body length, helping prevent u-joint binding on short shafts while maintaining full 70HP capacity.
Product appearance and specifications may vary slightly by batch. Compatibility may vary by serial number. Verify fitment before purchase.