Parker Chelsea 870 Series Power Take-Off

Quick Facts

Manufacturer: Parker Hannifin — Chelsea Products Division
Product Series: Chelsea 870 Series
Product Type: Hydraulic PowerShift power take-off
Mounting Pattern: Ten-bolt transmission opening
Primary Transmission Type: Heavy-duty automatic transmissions
Primary Transmission Family: Application-specific Allison automatic transmissions
Available Ratios: Nine
Maximum Continuous Torque: 670 lb-ft, depending on ratio
Maximum Published Power at 1,000 Output RPM: 128 horsepower, depending on ratio
Shift System: 12- or 24-volt electric-over-hydraulic
Output Options: Thirteen direct-pump and driveline configurations
Available Technologies: Wet Spline, Electronic Overspeed Control, Quiet Gear, Smart Start, and shaft-brake configurations
Approximate Weight: 56 pounds
Primary Applications: Fire and rescue, refuse, vacuum trucks, oil and gas equipment, and snow-and-ice-control vehicles
Production Status: Obsolete legacy product; current parts support and replacement options must be confirmed with Parker Chelsea

Overview

The Parker Chelsea 870 Series Power Take-Off is a heavy-duty hydraulic PowerShift PTO designed for compatible automatic transmissions with a ten-bolt PTO opening. It transfers power from the transmission to a directly mounted hydraulic pump or auxiliary driveline.

The 870 Series combines a compact housing with nine internal speed ratios and continuous torque ratings reaching 670 lb-ft. Its multiple ratios allow installers to match the output speed more closely to the hydraulic pump or driven equipment.

Available equipment included wet-spline pump outputs, Electronic Overspeed Control, Quiet Gear input gearing, Smart Start engagement, shaft-brake configurations, and multiple driveline and direct-pump outputs.

Parker currently identifies the Chelsea 870 Series as obsolete. Existing vehicles may still use the PTO, and replacement components or service support may remain available. New installations and complete replacement units should be reviewed with Parker Chelsea or an authorized distributor to determine the appropriate current product.

Key Characteristics

Hydraulic PowerShift PTO design
Ten-bolt transmission mounting pattern
Compact housing
Nine internal speed ratios
Continuous torque ratings up to 670 lb-ft
Thirteen output options
12- and 24-volt electric-over-hydraulic shifting
Direct-pump and driveline outputs
Wet-spline pump-output options
Electronic Overspeed Control option
Quiet Gear input option
Smart Start option
Shaft-brake output configurations
Two primary assembly arrangements
Pressure-lubricated configurations
Legacy product requiring application-specific parts verification

Major Components

Compact PTO housing
Transmission input gear
Internal gear train
Hydraulic clutch assembly
Clutch piston
Hydraulic control valve
Electric shift solenoid
Output shaft
Output bearings
Direct-pump flange or driveline output
Wet-spline lubrication components when equipped
Shaft brake when specified
Smart Start components when equipped
Electronic Overspeed Control system when equipped
Oil seals and O-rings
Mounting studs and fasteners
Pressure-lubrication passages
Electrical wiring and connectors

Product Type and Construction

The Chelsea 870 is a transmission-mounted hydraulic PowerShift PTO. Its ten-bolt housing attaches to an approved PTO opening on a compatible automatic transmission.

Hydraulic pressure operates an internal clutch that connects the transmission-driven input gear to the PTO output. This design allows electrically commanded engagement without using a conventional mechanical shift lever or cable.

The compact housing was designed to reduce clearance problems around frame rails, exhaust components, transmission features, and body equipment. Two assembly arrangements permit the housing bulge and output area to be positioned for different chassis installations.

How the Power Take-Off Works

The PTO input gear is driven by a compatible gear inside the transmission. When the vehicle or body-control system sends an approved engagement request, the PTO solenoid and hydraulic valve direct pressure to the internal clutch piston.

The applied clutch connects the rotating input assembly to the PTO output shaft. The internal ratio determines the relationship between transmission drive speed and PTO output speed.

The output then powers a directly mounted hydraulic pump or transfers power through a companion flange and auxiliary driveline. When disengagement is requested, hydraulic pressure is released or redirected and the internal clutch disconnects the output.

Position and Function Within the Vehicle

The 870 Series mounts to a compatible ten-bolt PTO opening on the automatic transmission. The assembly arrangement, valve position, output orientation, and pump location depend on the selected model and available chassis clearance.

The PTO can supply power for:

High-flow hydraulic pumps
Refuse-body hydraulic systems
Vacuum pumps and blowers
Fire apparatus equipment
Rescue equipment
Oilfield service systems
Snowplows and material spreaders
Hydraulic cranes
Hydro-excavation equipment
Recovery equipment
Other heavy-duty vocational systems

Common Specifications

PTO Type: Hydraulic PowerShift power take-off
Mounting Pattern: Ten-bolt transmission opening
Transmission Application: Application-specific heavy-duty automatic transmissions
Available Ratio Codes: A, B, C, D, E, F, G, H, and J
Published Continuous Torque Range: 335 to 670 lb-ft, depending on ratio
Maximum Published Continuous Torque: 670 lb-ft or 908 N-m
Maximum Published Power at 500 Output RPM: 64 horsepower or 48 kilowatts
Maximum Published Power at 1,000 Output RPM: 128 horsepower or 95 kilowatts
Approximate Weight: 56 pounds or approximately 25 kilograms
Shift Options: 12- or 24-volt electric-over-hydraulic
Lubrication Options: Pressure lubrication, rotated valve-body arrangements, and wet-spline configurations
Assembly Arrangements: Right-side or left-side housing-bulge configurations
Output Types: SAE pump mounts, ISO pump mount, DIN flanges, and 1410 Series companion-flange configurations
Production Status: Obsolete; availability depends on remaining stock, service parts, remanufactured units, and approved replacement options
All specifications must be confirmed using the complete Chelsea model number and the exact transmission application.

Power, Torque, Speed, and Operating Capacity

The 870 Series was offered with nine ratios and ratio-dependent continuous torque ratings. The highest-rated A ratio carries a published continuous rating of 670 lb-ft.

Published continuous torque ratings by ratio are:

A ratio: 670 lb-ft
B ratio: 630 lb-ft
C ratio: 590 lb-ft
D ratio: 550 lb-ft
E ratio: 485 lb-ft
F ratio: 430 lb-ft
G ratio: 380 lb-ft
H ratio: 355 lb-ft
J ratio: 335 lb-ft

The PTO does not require a continuous-duty derating when operated within the published rating for its ratio. The hydraulic pump, auxiliary driveline, and driven equipment may have lower continuous ratings and must be evaluated separately.

Intended Transmission and Mounting Position

The 870 Series was developed for compatible heavy-duty automatic transmissions with a ten-bolt PTO opening. Transmission identification is required because the bolt pattern alone does not confirm input-gear, lubrication, control, or mounting compatibility.

The following information must be verified:

Transmission manufacturer
Transmission model and serial number
Transmission specification
PTO-opening location
Transmission PTO-drive gear
Required input option
Selected internal ratio
Housing assembly arrangement
Valve-body orientation
Output rotation
Pump and chassis clearance
Transmission lubrication requirements

PTO Engagement and Shift System

The 870 Series uses an electric-over-hydraulic PowerShift system. Electrical power activates a hydraulic control valve that applies transmission pressure to the PTO clutch.

Published shift arrangements included:

12-volt electric-over-hydraulic shift
24-volt electric-over-hydraulic shift
12-volt shift without an installation kit
24-volt shift without an installation kit
12-volt shift with Electronic Overspeed Control
24-volt shift with Electronic Overspeed Control
12-volt remote hydraulic valve
24-volt remote hydraulic valve

The exact engagement procedure depends on the transmission, vehicle programming, PTO controls, and body equipment.

Power Transfer and Output Design

The 870 Series was offered with thirteen outputs covering direct-mounted hydraulic pumps and remotely mounted driven equipment.

Output families included:

1410 Series companion flange
DIN 120 driveline flange
DIN 100 driveline flange
Shaft-brake DIN 120 flange
Shaft-brake DIN 100 flange
Shaft-brake 1410 Series companion flange
Smart Start DIN 120 flange
Smart Start DIN 100 flange
Smart Start 1410 Series companion flange
Rotatable SAE B flange with SAE BB shaft
Rotatable SAE B flange with SAE C shaft
Rotatable SAE C flange with SAE C shaft
Rotatable ISO 7653 pump mount with DIN 5462 shaft

Direct-mounted pump outputs must match the pump flange, pilot, shaft, spline, rotation, speed, and torque requirements. Driveline outputs require correct alignment, universal joints, guarding, and critical-speed analysis.

Wet Spline, Smart Start, and Shaft-Brake Options

Wet Spline directs lubricant to the connection between the PTO output shaft and hydraulic-pump input shaft. This helps reduce fretting, corrosion, and spline wear.

Smart Start was offered for applications requiring reduced shock loading during engagement. It moderates how power is applied to compatible driven equipment rather than applying the full load abruptly.

Shaft-brake configurations help stop or control output-shaft rotation after disengagement. This can be important where residual rotation affects the driven equipment or operating procedure.

These systems were optional and configuration-specific. Their presence must be confirmed from the complete PTO model number rather than assumed from the 870 Series designation.

Hydraulic Circuit and Equipment Integration

The 870 Series can power high-capacity hydraulic systems, but the PTO ratio, engine speed, pump displacement, system pressure, required flow, and duty cycle must be calculated together.

A complete hydraulic circuit may include:

Direct-mounted hydraulic pump
Hydraulic-fluid reservoir
Suction hose and shutoff valve
Pressure and return lines
Directional-control valves
Pressure-relief valve
Hydraulic cylinders or motors
Pressure and return filtration
Hydraulic-oil cooler
Temperature and pressure sensors
Body-control interlocks
Engine-speed controls

The complete system must remain within the ratings of the PTO, transmission, pump, hoses, valves, reservoir, and driven equipment.

Housing, Shaft, Bearing, and Clutch Design

The 870 Series uses a compact housing intended to reduce installation interference. High-capacity bearings and heavy-duty gear designs support its ratio-dependent continuous torque ratings.

The hydraulic clutch connects and disconnects the PTO output without using a manual sliding-gear engagement system. The clutch, input gear, output shaft, bearings, control valve, and seals depend on correct hydraulic pressure and lubrication.

Two housing assembly arrangements allow the main housing bulge to be positioned differently on the right or left side of the installation.

Controls and Electronic Integration

The PTO control system may communicate with the transmission controller, engine controller, vehicle electrical system, and vocational-body controls.

Possible control functions include:

Dash-mounted PTO engagement switch
PTO indicator lamp
Transmission PTO-request circuit
Electric hydraulic-control solenoid
Parking-brake interlock
Transmission-range interlock
Vehicle-speed interlock
Engine-speed control
Remote throttle
Body-equipment interlock
Electronic Overspeed Control
Automatic PTO disengagement

Controls and wiring must match the exact vehicle voltage, transmission, PTO shift package, and body system.

Electronic Overspeed Control and Quiet Gear

Electronic Overspeed Control was available to help protect hydraulic pumps and driven equipment from excessive PTO output speed. The system monitors operating conditions and can disengage or limit PTO operation when its configured threshold is exceeded.

Quiet Gear was an available input option designed to reduce PTO gear noise in compatible transmission applications. The special input must match the transmission’s PTO drive gear and cannot be substituted without confirming the complete application.

The presence and settings of these features should be confirmed from the PTO model number, installation kit, wiring, and vehicle programming.

Efficiency, Heat, and Lubrication

The 870 Series was offered with pressure-lubricated and wet-spline configurations. Correct transmission-fluid type, level, pressure, and temperature are essential for the gears, bearings, clutch, and output system.

Valve-body arrangements could be rotated to improve chassis clearance. Rotation and lubrication codes must be matched to the complete PTO specification.

Excessive torque, overspeed, clutch slip, low lubrication pressure, contaminated fluid, or hydraulic-system inefficiency can create abnormal heat and shorten PTO life.

Duty Cycle and Operating Conditions

The 870 Series was designed for continuous-duty applications without requiring the PTO to be derated below its published ratio-specific continuous torque rating.

Application suitability depends on:

Selected ratio
Required continuous torque
Peak and shock loads
Output speed
Hydraulic-pump displacement
System pressure
Hydraulic-fluid temperature
Transmission lubrication
Vehicle movement during operation
Ambient conditions
Pump weight and support
Driven-equipment duty cycle

The PTO’s continuous-duty capability does not automatically make every pump, hose, valve, driveline, or driven component suitable for continuous operation.

Mounting and Installation

The 870 Series mounts to an approved ten-bolt transmission opening. Installation requires the correct input gear, ratio, assembly arrangement, mounting hardware, lubrication system, controls, and output.

The installer must verify:

Correct PTO and transmission combination
Correct input option
Required internal ratio
Proper mounting surface and gasket
Correct gear backlash
Assembly arrangement
Valve-body orientation
Output rotation
Pump or driveline clearance
Electrical-system voltage
Hydraulic shift-pressure supply
Pressure-lubrication connections
Pump support requirements
Transmission-fluid level after installation
Transmission-controller programming

A heavy direct-mounted pump may require a properly designed support bracket. Allowing excessive pump weight or hose loading to act on the PTO output can damage the housing, bearing cap, transmission case, or spline connection.

Transmission and Vehicle Compatibility

The Chelsea 870 Series must be matched to the exact automatic transmission and vehicle. A ten-bolt opening does not by itself establish compatibility.

Compatibility depends on:

Transmission manufacturer
Transmission model and specification
PTO-opening location
Transmission drive-gear design
PTO input option
Selected ratio
Lubrication pressure and flow
Transmission software
Vehicle electrical voltage
Frame and crossmember clearance
Exhaust-system placement
Pump dimensions
Body and equipment layout

Because the 870 Series is obsolete, a replacement PTO should not be selected solely by matching the former torque rating or ten-bolt mounting pattern.

Pump, Driveshaft, and Driven-Equipment Compatibility

A direct-mounted hydraulic pump must match the PTO flange, pilot, shaft, spline, rotation, speed range, torque demand, and mounting dimensions.

Driveline configurations require a compatible DIN or 1410 Series flange, properly sized driveshaft, correct universal-joint angles, sufficient slip travel, critical-speed analysis, and guarding.

The complete system is limited by the lowest-rated PTO, pump, shaft, flange, universal joint, hydraulic component, or driven-equipment rating.

Hydraulic Fluid, Filtration, and Reservoir Compatibility

The hydraulic system should use fluid that meets the pump and equipment manufacturers’ viscosity, temperature, and additive requirements.

The reservoir, suction line, filters, breathers, return plumbing, and oil cooler must support the required flow without excessive restriction, aeration, backpressure, or heat.

Contaminated, aerated, or overheated hydraulic fluid can damage the pump and increase the load placed on the PTO.

Common Applications

Fire apparatus
Rescue vehicles
Refuse trucks
Vacuum trucks
Hydro-excavation trucks
Oilfield service vehicles
Snowplows
Salt and material spreaders
Hydraulic-crane trucks
Recovery vehicles
Municipal equipment
Heavy-duty wet-line systems
Specialized vocational trucks

Advantages

Continuous torque ratings up to 670 lb-ft
No continuous-duty torque derating within the published rating
Nine internal speed ratios
Thirteen output options
Compact housing
Two assembly arrangements
Wet-spline pump-output options
Electronic Overspeed Control option
Quiet Gear input option
Smart Start engagement option
Shaft-brake configurations
12- and 24-volt controls
Direct-pump and driveline outputs
Designed for demanding vocational applications

Limitations or Considerations

The 870 Series is an obsolete legacy product
Complete new PTO availability may be limited
Replacement components must match the exact model
Current replacement PTOs may require changes to controls or installation
Torque capacity varies by ratio
Transmission compatibility must be confirmed
Gear backlash must be correctly established
Hydraulic shift pressure must meet requirements
Some applications require pressure lubrication
Heavy pumps may require structural support
Wet-spline outputs require proper lubrication
Electronic controls may require diagnosis or replacement
The ten-bolt pattern alone does not confirm interchangeability

Driver and Operator Experience

A correctly installed 870 Series PTO should provide controlled push-button engagement and stable power for heavy-duty hydraulic equipment.

Operators should monitor:

PTO engagement confirmation
Engine and output speed
Hydraulic pressure
Hydraulic-fluid temperature
Transmission temperature
Abnormal gear or clutch noise
Pump or driveline vibration
Unexpected disengagement
Slow equipment response
Fluid leakage
Electronic Overspeed Control warnings
Transmission or body-controller faults

PTO Engagement and Operating Procedure

The engagement procedure depends on the transmission, vehicle programming, PTO control system, and powered equipment. Operators must follow the instructions supplied for the exact vehicle.

A typical stationary procedure may require the parking brake to be applied, the transmission placed in an approved range, vehicle speed reduced to zero, and the engine returned to idle before the PTO request is activated.

After engagement is confirmed, engine speed should be increased only to the level required by the hydraulic pump or equipment. Electronic Overspeed Control should not be treated as a substitute for correct operator control or PTO-ratio selection.

Before road travel, the PTO should be disengaged when required and the body or auxiliary equipment secured in its transport position.

Inspection and Wear Points

PTO housing and mounting surface
Mounting studs and fasteners
Input gear and gear contact pattern
Gear backlash
Hydraulic clutch assembly
Output bearings
Output shaft and splines
Wet-spline lubrication system
Pump flange and pilot
Hydraulic control valve
Electric shift solenoid
Pressure-lubrication lines
Wiring and connectors
Electronic Overspeed Control components
Pump support brackets
Companion flange and auxiliary driveline
Oil seals and O-rings

Lubrication Requirements

The 870 Series requires the correct transmission lubricant, operating level, pressure, and temperature. The gears, bearings, hydraulic clutch, and output system depend on the transmission lubrication circuit.

Wet-spline configurations direct lubricant to the PTO-and-pump spline connection. The lubrication path must remain open, correctly sealed, and free of restrictions.

Pressure-lubrication lines and fittings should be checked for leakage, kinks, abrasion, damage, and internal restriction.

Maintenance and Ownership Notes

Routine maintenance should include checking mounting fasteners, transmission lubricant, hydraulic-control pressure, electrical connections, output splines, pump support, pressure-lube lines, and auxiliary-driveline components.

Because the 870 Series is obsolete, owners should record all identification information before a failure occurs. Replacement parts should be investigated before disassembling a serviceable unit.

Changes in engagement time, noise, temperature, vibration, or hydraulic performance should be diagnosed promptly. Continuing to operate a slipping clutch, damaged spline, worn bearing, or poorly lubricated PTO can damage the transmission and powered equipment.

Common PTO and Hydraulic-System Problems

PTO will not engage: Insufficient hydraulic pressure, a failed solenoid, damaged wiring, incorrect transmission programming, an unsatisfied interlock, or internal clutch damage may prevent engagement.
PTO will not disengage: A sticking control valve, trapped hydraulic pressure, an electrical fault, or damaged clutch components may keep the output engaged.
Clutch slips under load: Low apply pressure, contaminated fluid, worn clutch components, excessive torque, high temperature, or an internal hydraulic leak may cause slipping.
Gear noise: Incorrect backlash, incompatible input gearing, bearing wear, damaged gear teeth, or insufficient lubrication can produce abnormal noise.
Wet-spline wear: Insufficient lubrication, pump movement, misalignment, incorrect shaft geometry, or a loose support bracket may damage the PTO and pump splines.
Overheating: Excessive torque, overspeed, clutch slip, restricted lubrication, hydraulic inefficiency, or inadequate cooling can raise operating temperature.
Slow hydraulic operation: An incorrect PTO ratio, low engine speed, pump wear, suction restriction, low hydraulic-fluid level, internal leakage, or a relief-valve problem may reduce performance.
Electronic-control fault: Failed wiring, connectors, speed sensors, control modules, solenoids, or incorrect programming may cause intermittent operation or unwanted disengagement.

Safety and Service Precautions

Before servicing the PTO or hydraulic system, shut down the engine, secure the vehicle, relieve hydraulic pressure, disconnect electrical power when required, and prevent the driven equipment from moving.

Never work beneath a raised body, crane, aerial device, outrigger, or hydraulically supported component without the manufacturer’s approved mechanical blocking or support system.

Auxiliary drivelines must be properly guarded. Hands, clothing, tools, and loose objects must be kept away from rotating shafts, flanges, and universal joints.

PTO installation, backlash adjustment, hydraulic-pressure testing, internal repair, and transmission programming should be completed by qualified personnel using the correct service information.

Identification Information

The complete Chelsea model number identifies the PTO series, mounting option, ratio, transmission input, lubrication configuration, shift system, assembly arrangement, and output.

Record the following information before ordering parts or evaluating a replacement:

Complete Chelsea PTO model number
PTO serial or production information
Vehicle identification number
Truck manufacturer and model
Transmission manufacturer
Transmission model and serial number
Transmission specification
PTO-opening position
Ratio code
Input option
Lubrication code
Shift-option code
Assembly arrangement
Output-option code
Wet Spline, Smart Start, shaft brake, or EOC equipment
Hydraulic-pump manufacturer and model
Driven-equipment requirements

Do not order replacement parts or a substitute PTO from appearance or the 870 Series number alone.

Buying Considerations

Confirm whether the existing PTO can be repaired
Verify current parts availability before disassembly
Record the complete 870 Series model number
Identify the exact transmission
Determine the required continuous and peak torque
Calculate the required pump speed
Match the original ratio or properly redesign the system
Confirm the input gear and mounting arrangement
Match the pump flange and shaft
Identify all electronic-control features
Confirm Wet Spline, Smart Start, shaft-brake, and EOC requirements
Verify 12- or 24-volt controls
Check chassis and pump clearance
Evaluate current Parker replacement options
Confirm whether wiring, plumbing, programming, or brackets must change
Use a qualified PTO and hydraulic-system specialist

Variants and Configurations

Nine internal ratio options
Standard and Quiet Gear inputs
Pressure-lubricated models
Wet-spline models
Valve body in standard position
Valve body rotated 120 degrees
Valve body rotated 240 degrees
12-volt electric-over-hydraulic shift
24-volt electric-over-hydraulic shift
Electronic Overspeed Control packages
Remote hydraulic-valve configurations
Two assembly arrangements
SAE direct-pump outputs
ISO direct-pump output
DIN driveline flanges
1410 Series companion flange
Smart Start outputs
Shaft-brake outputs

Comparison to Similar Equipment

Compared with the Parker Chelsea 280 Series Power Take-Off, the 870 provides substantially higher ratio-dependent continuous torque capacity. Both use ten-bolt transmission mounting, but they serve different power requirements and use different components.

Compared with the Parker Chelsea 590 Series Power Take-Off, the 870 is a side-mounted ten-bolt PTO with nine ratios. The 590 is a rear-mounted PTO with a fixed 1:1 ratio for a narrower group of transmissions.

Compared with the Parker Chelsea 489 Series Power Take-Off, the 870 is a hydraulic PowerShift PTO for automatic transmissions and continuous heavy-duty service. The 489 is primarily a mechanically shifted eight-bolt PTO for manual-transmission applications.

Because the 870 Series is obsolete, comparisons with current PTOs must include transmission compatibility, control changes, mounting geometry, output speed, torque, pump interface, and replacement-parts support.

Best Fit For

Vehicles originally equipped with a Chelsea 870 Series PTO
Fleets maintaining legacy vocational trucks
Approved ten-bolt automatic-transmission applications
Continuous-duty hydraulic systems
Applications requiring multiple output-speed choices
Fire and rescue apparatus
Refuse trucks
Vacuum and hydro-excavation equipment
Oilfield service vehicles
Snow-and-ice-control trucks
Operators with access to experienced PTO service support
Applications where compatible service parts remain available

Related Vehicle and Trailer Types

Related Truck and Trailer Models

Related PTO and Hydraulic System Types

Related PTO and Hydraulic Products

Related Equipment Systems

Related Guides

Regulatory and Compliance Notes

PTO and hydraulic-system installations must preserve the vehicle’s braking, steering, transmission, driveline, electrical, exhaust, emissions, fuel-system, and structural integrity.

The completed vehicle must remain within its axle, frame, tire, wheel, transmission, driveline, and gross vehicle weight ratings. Installing or replacing a PTO does not increase any certified vehicle rating.

Hydraulic hoses, rotating shafts, raised bodies, cranes, vacuum equipment, and other powered systems may be subject to workplace-safety, inspection, guarding, and operating requirements.

Changes made while replacing an obsolete 870 Series PTO must be reviewed for proper controls, output speed, hydraulic performance, equipment safety, and completed-vehicle compliance.

Real World Operating Notes

The 870 Series should be treated as a complete configured system rather than a generic ten-bolt PTO. Ratio, input gear, controls, lubrication, assembly arrangement, and output all affect compatibility.

A replacement PTO with the same maximum torque rating may still produce the wrong output speed or require different controls. Hydraulic flow and equipment speed should be recalculated whenever the PTO ratio changes.

Wet-spline lubrication can substantially reduce pump-shaft wear, but it must remain properly supplied and sealed. Dry splines, red fretting debris, oil leakage, or pump movement indicate a problem requiring inspection.

Because this is an obsolete product, owners should preserve identification tags, service records, wiring diagrams, installation instructions, and removed components until the repair or replacement has been completed successfully.

Frequently Asked Questions

What is the Parker Chelsea 870 Series PTO?

It is a ten-bolt hydraulic PowerShift PTO designed for compatible heavy-duty automatic transmissions and vocational hydraulic equipment.

Is the Chelsea 870 Series still in production?

Parker currently identifies the 870 Series as obsolete. Service parts, remaining inventory, remanufactured units, or application-specific replacements may still be available.

How much torque can the 870 Series handle?

The maximum published continuous rating is 670 lb-ft. Actual capacity ranges from 335 to 670 lb-ft depending on the selected ratio.

How many ratios were available?

The 870 Series was offered with nine internal speed ratios.

Is the 870 Series rated for continuous operation?

Yes. Parker published continuous torque and horsepower ratings for each ratio without requiring an additional PTO derating for continuous-duty use.

What is Electronic Overspeed Control?

Electronic Overspeed Control is an optional protection system designed to help prevent the PTO or driven equipment from operating above a configured speed limit.

What is Smart Start?

Smart Start is an optional engagement system intended to reduce shock loading when power is initially applied to compatible driven equipment.

Can the 870 directly mount a hydraulic pump?

Yes. Rotatable SAE and ISO direct-pump outputs were available, including wet-spline configurations.

Can any ten-bolt PTO replace the 870 Series?

No. The replacement must match the transmission, input gearing, ratio, rotation, torque, lubrication, controls, mounting clearance, and output requirements.

How is the correct replacement identified?

Use the complete Chelsea model number, transmission identification, ratio, input option, lubrication code, shift system, assembly arrangement, output, pump information, and driven-equipment requirements.

Availability and Where to Find

The Parker Chelsea 870 Series is an obsolete legacy product. Existing units may remain in operation, and selected service parts, repair components, remaining inventory, or remanufactured assemblies may be available.

Parts and application assistance may be available through Parker Chelsea distributors, commercial-truck dealers, PTO specialists, hydraulic-equipment suppliers, body builders, and heavy-duty repair facilities.

Before ordering, buyers should provide the complete PTO model number, transmission information, vehicle VIN, hydraulic-pump information, and driven-equipment requirements.

Current product status, technical support, parts information, and replacement guidance are available through the Parker Chelsea website.

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