Description
A838X – POWER CLUSTER – AIR/HYDRAULIC ACTUATOR
PART NUMBER(S):
Fleet Products: A838X, A838 | OE: FE2704 | 6510L, 6510R, 6510
DESCRIPTION:
Model: A838X / A838 – Brake Actuator Power Cluster with Master Cylinder 6" long X 1-1/2" dia. (FE2704)
Vehicles: Medium and Heavy-Duty Trucks & Trailers
• Type: Air-over-hydraulic brake booster
• Application: Air/hydraulic brake systems
• Dimensions: 6.00 in air chamber diameter
• Dimensions: 4.00 in air chamber length
• Stroke: 2.5 in
• Diaphragm Type: Type 24
• Bore Diameter: 1.50 in
• Hydraulic Volume: 3.5 in³
• Output Pressure: 1000 PSI
• Inlet Fitting: 5/16 in inverted flare
• Master Cylinder Casting: FE2704
• Mounting: Left-side bracket, horizontal orientation recommended
• Material: Wagner-style assembly
• Performance: Pneumatic-to-hydraulic brake assist
• Features: Internal residual check valve, leak/performance tested, compatible with DOT 3/DOT 4/DOT 5/DOT 5.1 fluids and mineral-based hydraulic oils
Applications:
Designed for legacy and retrofit installations on medium to heavy-duty vehicles, especially where intermittent pneumatic assistance is required. Commonly found in trailers, loaders (e.g., Clark Michigan 75B), and specialized vocational truck systems using air/hydraulic brake conversions.
CROSS-REFERENCE(S):
A838, A838X, 6510L, 6510R, 6510, A839, A840, 65-840L, 65-840R, AF838, AF839, AF840, 6510-1, 6510-2, 6510-3, 6510-4, 6510-5, 6510-6, 6510-7, 6510-8, 6510-9, 6510-10, 6510-11, FE2704
A cross-reference listing means the part can be used as a direct or functional replacement for the listed part numbers.
IMPORTANT INSTALLATION NOTES:
✔ Install in horizontal orientation to prevent internal seal failure or air entrapment
✔ Lubricate pivot point periodically to maintain performance
✔ Bleeding required after installation to remove trapped air from hydraulic system
✔ Use only fluid types compatible with the original system spec
✔ Confirm correct bracket side – A838X mounts on left-side
SOLD AS REMANUFACTURED | CORE RETURN REQUIRED
Built to OEM standards | thoroughly cleaned, inspected, and tested to ensure durability, performance, and reliability in demanding applications.
Warranty Information
