AM131779 PTO Clutch Replacement for John Deere 325, 335, 345, GX335, GX345, GX355 | Ogura MA-GT-JD23BF

Overview

This AM131779 PTO clutch replacement is an aftermarket electric PTO clutch for select John Deere lawn and garden tractor applications, including John Deere 325, 335, 345, GX335, GX345, and select GX355 models. It replaces John Deere AM131779 and AM126102, and cross-references Ogura MA-GT-JD23BF, Ogura MA-GT-JD23, Stens 255-831X, and Rotary 15779.

Built with a 1-1/8 inch crankshaft bore, 5-5/16 inch pulley diameter, counter-clockwise rotation, and pulley compatibility for 1/2 inch or 5/8 inch belts, this clutch is designed to restore reliable mower deck blade engagement when matched to the correct tractor, serial range, and original clutch number.

Important fitment warning: Serial number and crankshaft bore matter on these John Deere platforms. Many GX335 and GX345 applications use this clutch only through serial number 120,000. Later tractors may use a different 1-inch bore clutch. For GX355 models, verify the original clutch number or measure the crankshaft bore before ordering.

Key Features

• Aftermarket electric PTO clutch replacement for listed John Deere lawn and garden tractors
• Crankshaft Bore: 1-1/8" / 1.125"
• Pulley Diameter: 5-5/16"
• Belt Width: accepts 1/2" or 5/8" belt
• Rotation: CCW from pulley side
• Voltage: 12V DC
• Integrated brake assembly for controlled blade stopping
• Fully assembled and ready to install

Compatible Brands & Models

This PTO clutch fits select John Deere 300 Series and GX Series lawn and garden tractors. Fitment depends on serial number, original clutch number, and crankshaft bore.

John Deere Applications

• John Deere 325: verify original clutch number before ordering
• John Deere 335: AM131779 clutch applications
• John Deere 345: serial number 070,001 and higher
• John Deere GX335: serial number 120,000 and lower
• John Deere GX345: serial number 120,000 and lower
• John Deere GX355: verify serial range, original clutch number, and 1-1/8 inch crankshaft bore before ordering

Serial number note: Do not choose this clutch by model number alone. If your original clutch is marked AM131779, AM126102, MA-GT-JD23BF, or MA-GT-JD23, this is the correct replacement path. If your tractor has a 1-inch crankshaft, this 1-1/8 inch bore clutch is not correct.

Replaces OEM Part Numbers

• John Deere: AM131779
• John Deere: AM126102

Fitment note: AM131779 is commonly used as the replacement path for AM126102 on compatible John Deere applications. Always confirm by the original clutch number, tractor serial number, and crankshaft bore.

Cross-Reference Aftermarket Numbers

• Ogura: MA-GT-JD23BF
• Ogura: MA-GT-JD23
• Stens: 255-831X
• Rotary: 15779

Search note: Ogura numbers may also appear without hyphens, such as MAGTJD23BF or MAGTJD23. Match the original clutch number, bore size, pulley diameter, belt width, rotation, and connector style before ordering.

What’s Included

• Complete electric PTO clutch assembly
• Factory-balanced 5-5/16" pulley
• Pre-installed bearing assembly
• Encapsulated electromagnetic coil
• Integrated brake assembly
• Wiring lead and connector as shown in product photos

Before Installing

Before installing a new PTO clutch, inspect the mower deck drive system and clutch mounting area. A new clutch can fail early if the belt is misrouted, an idler is seized, a spindle is dragging, or the anti-rotation bracket is damaged.

• Confirm your tractor model and serial number before ordering
• Match the original clutch number to AM131779, AM126102, MA-GT-JD23BF, or MA-GT-JD23
• Measure the crankshaft if your GX-series serial number is near a known cutoff
• Check the deck belt for glazing, cracking, oil contamination, or stretch
• Confirm belt routing around the clutch pulley, idlers, and spindle pulleys
• Inspect idler pulleys and blade spindles for drag, wobble, or bearing noise
• Check the wiring connector for corrosion, melting, loose terminals, or damage
• Make sure the crankshaft is clean and free of rust, burrs, or keyway damage

If the old clutch will not slide off the crankshaft, do not pry against the pulley or hammer. See the PTO clutch stuck on crankshaft guide before removal turns into crankshaft damage.

Why Buy From PTO Direct USA?

• Fast USA shipping
• Fitment guarantee
• 1-year warranty
• Fitment-first product support
• Clear product images for easier clutch identification
• Trusted replacement supplier for homeowners, repair shops, and mower service professionals

FAQ

Does AM131779 fit a John Deere GX345?

Yes, this clutch fits many John Deere GX345 tractors through serial number 120,000. If your GX345 is serial number 120,001 or higher, verify the crankshaft bore and original clutch number before ordering because later units may use a different 1-inch bore clutch.

Does AM131779 fit a John Deere 345?

This clutch is commonly listed for John Deere 345 tractors with serial number 070,001 and higher. Early 345 models may use a different PTO clutch, so check the tractor serial number and original clutch label before ordering.

Does AM131779 fit a John Deere GX355?

Some GX355 applications are associated with the AM131779 clutch family, but GX355 serial ranges can be inconsistent across catalogs. GX355 owners should verify the original clutch number or confirm a 1-1/8 inch crankshaft bore before ordering.

Does AM131779 replace AM126102?

Yes. AM131779 is commonly used as the replacement path for AM126102 on compatible John Deere applications.

Is Ogura MA-GT-JD23BF the same fitment as AM131779?

Ogura MA-GT-JD23BF is the Ogura reference commonly associated with the John Deere AM131779 clutch family. You may also see it listed as MA-GT-JD23, MAGTJD23BF, or MAGTJD23.

What bore size does this PTO clutch use?

This clutch uses a 1-1/8 inch bore, also written as 1.125". If your tractor has a 1-inch crankshaft, this clutch is not correct.

What belt width does this clutch use?

This clutch pulley is commonly listed for 1/2 inch or 5/8 inch belt applications. Confirm your deck belt and original pulley style before ordering.

What are common signs of a failing PTO clutch?

Common symptoms include mower blades not engaging, the PTO clutch clicking but the blades not spinning, slipping under load, intermittent blade engagement, or blades slowing down after the mower heats up. A worn coil can work cold, then weaken after 10 to 30 minutes of mowing.

Can PTO Direct USA help me confirm fitment?

Yes. Email support@ptodirectusa.com with your mower model number, serial number, deck size, original clutch number, and clear photos of the old clutch. For the best fitment help, include photos of the clutch label or stamped number, wiring connector, pulley, anti-rotation bracket, and crankshaft area.

Need installation help? Read the PTO clutch installation guide.

Need a different John Deere clutch? Browse the John Deere PTO clutch collection or the full electric PTO clutch catalog.