PARKER CHELSEA 380123-12 — 12V NON-REGULATING SOLENOID CARTRIDGE VALVE FOR 277 / 278 / 859 / 867 SERIES POWERSHIFT PTOs
PRODUCT OVERVIEW
The Parker Chelsea 380123-12 is the 12-volt, 25-watt non-regulating solenoid cartridge valve for Chelsea Powershift (hydraulically shifted / hot shift) PTO units. This valve is the primary electrical-hydraulic control component in the 277, 278, 859, and 867 Series PTO engagement system. When the operator activates the PTO switch in the cab, a 12V DC signal energizes this solenoid cartridge, which opens and directs hydraulic oil pressure to the PTO's internal clutch pack — compressing the pack, locking the drive gear to the output shaft, and initiating PTO rotation. Chelsea (a division of Parker Hannifin Corporation) is the manufacturer of origin, and the 380123-12 is the genuine OEM part number. Also searched as Chelsea 380123-12, Parker 38012312, DS563CS12M1, Chelsea solenoid valve, and Parker PTO cartridge valve 12V.
WHY THIS VALVE FAILS — AND WHY IT MATTERS
The 380123-12 is a non-regulating (on/off) cartridge valve. It has two failure modes:
Coil failure: The internal electromagnetic coil burns out and no longer creates a magnetic field when energized. Result: the valve stays mechanically closed, no oil pressure reaches the clutch pack, and the PTO does not engage even though the dash switch is "on." A failed coil typically draws no current and produces no audible click at the solenoid.
Spool contamination or sticking: Hydraulic fluid contamination, sludge, or wear particles lodge in the precision-machined spool bore, preventing the spool from shifting fully open. Result: partial or sluggish PTO engagement, erratic engagement, or a PTO that engages slowly and loses torque under load.
Both failure modes are often misdiagnosed as pump, clutch pack, or hydraulic circuit problems. Replacement of this valve is the correct first diagnostic step when PTO engagement symptoms appear.
COMPATIBILITY — VERIFIED SERIES
Chelsea 277 Series (10-Bolt Transmission Aperture):
The 277 is Chelsea's heavy-capacity Powershift PTO for Allison World Transmissions using the 10-bolt mounting pattern. Applications include refuse collection trucks, dump trucks, fire apparatus, utility trucks, and other vocational equipment with Allison 3000 and 4000 Series automatics.
Chelsea 278 Series (10-Bolt Transmission Aperture):
The 278 shares the 277's 10-bolt interface with alternate output configurations. Same solenoid valve applies.
Chelsea 859 Series:
The 859 is Chelsea's high-torque Powershift PTO for applications requiring greater load capacity than the 277/278 — specifically fire and rescue, refuse, and oil field applications. Per Parker's own product documentation, the 859 offers the sealing integrity of a 10-bolt pattern. The 380123-12 applies to these units.
Chelsea 867 Series:
The 867 is in the same high-capacity Powershift family as the 859.
DOES NOT FIT:
Chelsea 230 Series PTOs
Chelsea 270 Series PTOs
Any 6-bolt PTO aperture unit
Always confirm your PTO's model number from the Chelsea data tag before ordering. The data tag is typically located on the PTO housing and will show the series number as the first 3 digits of the model string.
CONNECTOR NOTE — WHITE vs. BLACK
The 380123-12 is the current "New Style" cartridge featuring a white connector housing. Some earlier-vintage Chelsea PTOs may use an older-style black connector cartridge. The two connector styles are electrically equivalent (same coil specs) but may not physically mate to the opposite harness without an adapter. Visually inspect your existing solenoid's connector shape and color before ordering. Both connector configurations use the same mounting cartridge thread and O-ring interface — only the coil/connector top differs.
SPECIFICATIONS
Part Number: 380123-12
Alternate Format: 38012312
Type: Non-Regulating Solenoid Cartridge Valve
Voltage: 12V DC
Wattage: 25W
Connector: White Top (New Style)
Function: On/Off (non-regulating) — controls hydraulic oil flow to PTO clutch pack
Compatible PTO Series: Chelsea 277, 278, 859, 867
Transmission Compatibility: Allison World Transmissions (3000 / 4000 Series and others with Chelsea Powershift PTOs)
Does NOT Fit: 230 / 270 Series (6-Bolt) PTOs
CROSS-REFERENCE LIST
Parker Chelsea Part Number: 380123-12
No-Hyphen Format: 38012312
OEM Cross-References: DS563CS12M1
Additional Cross-References: 380011-12, 38001112, 1544-0556 (verify each before ordering)
Traction.com Catalog Number: CHE380123-12
APPLICATIONS
The Chelsea 277 and 278 Powershift PTO is found on vocational trucks with Allison automatic transmissions in the following markets:
Refuse and recycling trucks (rear loader, side loader, front loader) — using the PTO to drive hydraulic packing/lifting circuits
Dump trucks — using the PTO to drive hoist hydraulic pumps
Fire apparatus — using the PTO for aerial, rescue pump, or aerial platform hydraulic systems
Utility and aerial lift trucks — using the PTO to power boom and outrigger circuits
Oil field service trucks — pump drives and auxiliary hydraulic circuits
Crane and boom truck chassis — using the PTO for crane hydraulic systems
Municipal and fleet equipment of all types equipped with Allison automatics and Chelsea Powershift PTOs
ABOUT CHELSEA / PARKER HANNIFIN
Chelsea is a product division of Parker Hannifin Corporation, one of the world's largest manufacturers of motion and control technologies. Chelsea Products Division has been manufacturing power take-off (PTO) systems for mobile vocational and truck markets for over 60 years, with products distributed through a global network of distribution centers in North America, Europe, Asia, and Australia. Their PTO products are specified by major vocational truck OEMs and transmission manufacturers including Allison Transmission as the matched PTO partner for Allison World Transmission platforms. Parker Hannifin Corporation is headquartered in Mayfield Heights, Ohio.