Best 1000 Pto To 540 Adapter for Tractor PTO Fit

#1 · Best Overall

1. Koch Industries 4045223

• Weight: 3.5 lb

Best for: Quick-release 21-to-6 spline conversion.

Why it ranks #1: It explicitly converts 1-3/8-inch, 21-spline 1000 RPM to 6-spline 540 RPM and includes a quick-release connection.

Koch Industries pairs a 21-spline female input with a 6-spline male output for the stated 1,000-to-540 RPM PTO conversion. Its quick-release spline adapter connects a tractor shaft to an implement, while the yellow zinc-plated finish and metal construction distinguish this option for buyers seeking a readily identifiable adapter.

The 1-3/8-inch by 21 female spline and 1-3/8-inch by 6 male spline specify the shaft interfaces for matching tractor and implement connections. Koch identifies the unit as a 21-spline, 1,000 RPM to 6-spline, 540 RPM adapter, making the intended conversion clear. Quick release can make the connection workflow simpler when changing compatible implements. The listed 3.5-pound weight and 7.03-inch dimension provide handling and space considerations; its yellow zinc-plated finish is also specified.

Skip it if you need a stated extension length or horsepower ceiling; Koch's listing supplies neither, while Eparts E-PA08 specifies both.

This suits tractor owners who need Koch's specified 21-to-6 spline, 1,000-to-540 RPM connection and value a quick-release format. Check PTO clearance against its listed 7.03-inch dimension, since the listing gives no extension length.

Listed on Amazon as: Koch Industries 4045223 PTO 21 Sp 1000 RPM to 6 Sp 540 RPM Quick Release Spline Adapter with 1-3/8 by 6-Inch Male Spline and 1-3/8 by 21-Inch Female Spline

#2 · Best OEM Option

2. SpeeCo S16061100

Best for: SpeeCo quick-release 75 HP conversion.

Why it ranks #2: This genuine SpeeCo quick-release adapter explicitly converts 21-spline 1000 RPM to 6-spline 540 RPM and is rated to 75 HP.

SpeeCo specifies a quick-release adapter that converts a 21-spline, 1,000 RPM PTO to a 6-spline, 540 RPM output, making the intended change explicit. Its 1-3/8-inch spline sizes and 75 HP maximum help buyers check both connection compatibility and operating limits before adding the listed 3-5/16 inches of extension.

The 1-3/8-inch by 21 male spline and 1-3/8-inch by 6 female spline identify the adapter's stated interfaces, while SpeeCo explicitly describes the 21-to-6, 1,000-to-540 RPM conversion. Quick-release construction supports a release-style connection workflow, and the 3-5/16-inch extension affects shaft reach without requiring buyers to infer its length. Yellow zinc dichromate plating is listed, and the 75 HP maximum marks the capacity boundary.

Skip it if you need more than 3-5/16 inches of added reach; Eparts E-PA08 lists a 4.125-inch extension for its adapter.

This is a good match for owners needing SpeeCo's stated 21-to-6 spline RPM conversion with a quick-release connection. Check that its 3-5/16-inch extension provides enough reach and that the application remains within 75 HP.

Listed on Amazon as: Genuine SpeeCo OEM PTO 6 To 21 Spline Adapter with Quick-Release

#3 · Large-Spline Fit

3. Reliable Aftermarket Large-Spline Adapter

• Weight: 4.4 lb

Best for: 100 HP large-spline conversion.

Why it ranks #3: It addresses a distinct 1-3/4-inch, 20-spline 1000 RPM input, converts to 1-3/8-inch, 6 spline, and lists capacity up to 100 HP.

A 1-3/4-inch, 20-spline input reduces to a 1-3/8-inch, 6-spline output on this Reliable Aftermarket Parts adapter, with the listing specifying 1,000-to-540 RPM use. Its stated application extends to universal tractors up to 100 HP, setting it apart for buyers whose input shaft matches the larger spline.

The large 1-3/4-inch by 20-spline input and 1-3/8-inch by 6-spline output define a different interface from adapters with a 1-3/8-inch, 21-spline female end. The listing says the large 1,000-to-540 spline reduces the PTO and adds 4-5/8 inches of shaft extension, which can support reach while changing the output connection. Its 7-1/2-inch overall length and stated up-to-100-HP application help buyers assess clearance and capacity.

Skip it if you have a 1-3/8-inch, 21-spline input; Koch Industries 4045223 lists that female spline size for its 21-to-6 conversion.

Choose this adapter when the tractor has the listed 1-3/4-inch, 20-spline input and the application needs a 1-3/8-inch, 6-spline output at 1,000-to-540 RPM. Confirm the 7-1/2-inch overall length fits the available space.

Listed on Amazon as: PTO Adapter, Replaces OEM Part Number X59109

#4 · 70 HP Option

4. Eparts E-PA08

Best for: 70 HP conversion with push-pin.

Why it ranks #4: Its 1-3/8-inch, 21-spline female and 6-spline male arrangement is explicitly listed as 1000-to-540 RPM, with a 70 HP maximum.

Its 21-spline female input and 6-spline male output convert 1,000 RPM to 540 RPM, giving owners of matching PTO equipment a direct speed-and-spline transition. The push-pin style keeps the connection approach straightforward, while its 4.125-inch extension adds useful shaft reach within a 70 HP limit.

The 1.375-inch female, 21-spline end and 1.375-inch male, 6-spline end specify the connection pattern for the stated 1,000-to-540 RPM conversion. Its 4.125-inch extension can add reach between the tractor PTO and implement, and the 6.375-inch overall length gives a concrete dimension to consider when checking available clearance. Push-pin construction is the listed connection style; the 70 HP maximum sets an important operating boundary for the application.

Skip it if you need a higher horsepower limit; this adapter is capped at 70 HP, while Reliable Aftermarket Parts X59109 lists applications up to 100 HP.

Choose this Eparts adapter when a compatible 21-spline, 1,000 RPM PTO must connect to a 6-spline, 540 RPM implement, and its 4.125-inch extension suits the setup. Keep the 70 HP maximum in view.

Listed on Amazon as: Eparts, Inc. Push-Pin PTO Adapter, Female 1-3/8" & 21 Spline, Male 1-3/8" & 6 Spline, 70HP (1.375 Inch Female, 1.375 Inch Male) – E-PA08

#5

5. Reliable Aftermarket Clamp-Bolt Adapter

• Weight: 3.2 lb

Best for: Clamp-bolt 21-to-6 connection.

Why it ranks #5: The 21-spline female and 6-spline male arrangement matches the conversion direction, and the listing specifies a clamp bolt and up to 70 HP.

A clamp-bolt connection distinguishes this Reliable Aftermarket Parts adapter, which lists a 1-3/8-inch, 21-spline female end and a 1-3/8-inch, 6-spline male end. It adds 4-5/16 inches of length and is rated up to 70 HP, giving buyers concrete connection and reach details for a standard-duty application.

The 21-spline female and 6-spline male ends specify the shaft interfaces, while the clamp bolt identifies the connection type rather than a push-pin release. Its listed 4-5/16-inch increase in length can add reach, and the standard-duty designation plus up-to-70-HP rating define the stated application boundary. The supplied information does not specify an RPM conversion, so buyers should treat this as a spline adapter and rely on its listed connection details rather than assume a speed change.

Skip it if you require a stated RPM reduction; SpeeCo S16061100 explicitly lists conversion from 1,000 RPM to 540 RPM.

Consider this adapter when the equipment needs its listed 21-female, 6-male spline arrangement and a clamp-bolt connection, within the 70 HP limit. The listing gives reach and duty details but does not specify RPM conversion.

Listed on Amazon as: PTO Adapter with Clamp Bolt – Replaces OEM Part Number 033200087

#6

6. Mkekexe P01

Best for: Hardened-alloy push-pin conversion.

Why it ranks #6: Its 1-3/8-inch, 21-spline female and 6-spline male sides match the conversion direction; the listing gives a 70 HP limit and 4.125-inch extension.

Mkekexe specifies hardened, high-strength alloy steel for this push-pin extender, alongside a 21-spline female input and 6-spline male output. The listed 4.125-inch extension and 70 HP ceiling help buyers assess reach and capacity, while the stated spline direction matches a 1,000-to-540 PTO conversion layout.

The 1-3/8-inch, 21-spline female and 1-3/8-inch, 6-spline male ends identify the interfaces for the listed PTO arrangement. Mkekexe describes hardened alloy steel for hardness and wear resistance, and says the regular spline shape and mating holes improve matching precision and stability. Those construction details relate to connection fit and wear, while the 4.125-inch extension, 6.5-inch overall length, and 70 HP maximum set practical reach, clearance, and capacity limits.

Skip it if you need a listed rating above 70 HP; Reliable Aftermarket Parts X59109 lists universal tractor applications up to 100 HP.

This fits buyers seeking a push-pin adapter with 21-female, 6-male splines and the listed 4.125-inch extension. The alloy-steel and precision-matching claims are specified, but check the 6.5-inch overall length and 70 HP limit against the application.

Listed on Amazon as: New PTO Extender for tractor, Female 1 3/8'' 21Spline, Male 1-3/8'' 6 Spline, 70HP, Push-Pin PTO Adapter quick connect for tractor

#7

7. Eparts E-PA26

Best for: 75 HP reverse-orientation adapter.

Why it ranks #7: Its 1-3/8-inch, 6-spline female and 21-spline male configuration reverses the searched conversion, despite its listed 75 HP maximum.

Its 75 HP maximum and 6.625-inch length make the Eparts E-PA26 straightforward to assess for a compatible PTO connection. The specified 1.375-inch female 6-spline and male 21-spline ends run opposite the 21-female-to-6-male layout needed for a 1,000-to-540 RPM adapter, so orientation is the key selection boundary.

Eparts lists a 1.375-inch, 6-spline female end and a 1.375-inch, 21-spline male end, identifying a reverse spline arrangement relative to a 21-to-6 conversion adapter. Buyers can use those dimensions to determine whether the PTO and implement interfaces match before planning an installation. The 6.625-inch length affects available space and reach, while the stated 75 HP maximum limits the application. The listing calls it a universal-application adapter but does not state an RPM conversion.

Skip it if you require a stated 1,000-to-540 RPM conversion; Eparts E-PA08 explicitly lists that conversion and the matching spline direction.

This E-PA26 fits buyers whose equipment calls for a 6-spline female to 21-spline male connection and stays within 75 HP. Its 6.625-inch length and reverse orientation make shaft clearance and interface match essential considerations.

Listed on Amazon as: Eparts, Inc. E-PA26 PTO Adapter, Female 1-3/8" & 6 Spline, Male 1-3/8" & 21 Spline, 75 HP

#8

8. BUYMACHINERYPARTS E-PA26

• Weight: 1 lb

Best for: 75 HP E-PA26 replacement connection.

Why it ranks #8: This push-pin E-PA26 has a 6-spline female and 21-spline male configuration, the opposite direction from 1000-to-540 conversion.

The E-PA26 listing gives a 6.625-inch length and a 75 HP maximum, useful checks for buyers assessing clearance and capacity. Its 1.375-inch, 6-spline female and 21-spline male ends are the reverse of a 21-to-6, 1,000-to-540 adapter, making this a fit for a different connection direction.

BUYMACHINERYPARTS specifies the female end as 1.375-inch, 6-spline and the male end as 1.375-inch, 21-spline, so the connection direction must match the equipment rather than the common 21-female-to-6-male conversion arrangement. The 6.625-inch length gives a concrete clearance measurement, and the 75 HP maximum sets the stated capacity boundary. It is a push-pin type and is identified as interchangeable with E-PA26; the listing recommends professional guidance for installation or replacement.

Skip it if you need the 21-spline female to 6-spline male direction; All States PA11 lists that orientation for its push-pin adapter.

This suits buyers replacing an E-PA26-style connection with matching 6-female, 21-male splines and an application within 75 HP. Its 6.625-inch length, reverse direction, and recommendation for professional installation are relevant fit and workflow limits.

Listed on Amazon as: BUYMACHINERYPARTS E-PA26 PTO Adapter, 75HP, Female 1-3/8" & 6 Spline, Male 1-3/8" & 21 Spline, (1.375 Inch Female, 1.375 Inch Male)

#9

9. Mkekexe Push-Pin Extender

• Weight: 3.39 lb

Best for: Push-pin extension for reverse spline orientation.

Why it ranks #9: Its 6-spline female and 21-spline male arrangement is opposite the desired direction, although it lists a 70 HP limit and 4.125-inch extension.

A 4.125-inch extension and 6.375-inch overall length are the concrete draws of this Mkekexe push-pin PTO extender, which adds reach for compatible tractor equipment. Its listed spline orientation is 6-spline female to 21-spline male, however, so it is not the 21-female-to-6-male orientation used for a 1,000-to-540 RPM adapter.

Mkekexe specifies a 1-3/8-inch, 6-spline female end and a 1-3/8-inch, 21-spline male end, a reverse orientation from a 21-spline input to 6-spline output conversion adapter. That distinction determines whether it can connect to the intended shaft and implement. The push-pin style is suited to its stated extender role, while the 4.125-inch extension can add reach. Its 70 HP maximum is another operating limit to account for when matching equipment.

Skip it if you need a 21-spline female input and 6-spline male output; Eparts E-PA08 lists that conversion orientation.

Consider it only when a compatible PTO setup needs an extension with this 6-female, 21-male spline orientation. Its stated 4.125-inch reach and 70 HP ceiling are useful boundaries, but it is not the requested reverse-direction conversion.

Listed on Amazon as: New PTO Extender Adaptor Push-Pin Type with 1-Pack PTO Power Take Off Pin Yoke Quick, Female 1-3/8"& 6 Spline, Male 1-3/8"& 21 Spline,70 HP PTO Shaft Extension Parts,PTO Quick Connect for Tractor

#10

10. All States Quick Connect Adapter

• Weight: 2.94 lb

Best for: All States quick-connect replacement.

Why it ranks #10: This product has a 6-spline female and 21-spline male configuration, so it reverses the searched conversion despite its quick-connect design.

All States lists a quick-connect adapter with a 6-spline female end, 21-spline male end, and 4-1/8-inch extension, making its connection direction and added reach easy to assess. Its named replacement references include PA-09, PA11, VTF6010, and XB371, while the listed tractor limit is 70 HP.

The 1-3/8-inch, 6-spline female and 1-3/8-inch, 21-spline male ends define a reverse orientation from a 21-female-to-6-male, 1,000-to-540 RPM adapter. Quick-connect construction and a 4-1/8-inch extension can suit a compatible PTO setup needing that connection and extra reach. All States lists an overall length of 5-7/8 inches and references PA-09, PA11, VTF6010, and XB371; its stated tractor limit is 70 HP.

Skip it if you need a 21-spline female input and 6-spline male output; Eparts E-PA08 lists that 1,000-to-540 conversion orientation.

This All States adapter suits buyers replacing a referenced PA-09, PA11, VTF6010, or XB371 part when the 6-female, 21-male orientation matches. Allow for its 5-7/8-inch overall length and keep the 70 HP limit in view.

Listed on Amazon as: All States PTO Adapter Push-Pin Type 1-3/8" 6 Spline Female 1-3/8" 21 Spline Male 75 HP fits PTO Drivelines & Parts PA11 PA-09 VTF6010 XB371