High-Frequency Clutch Master Cylinder for Toyota XUI3540A

CM246

Applicable Vehicle Models (Application)
This product spans both the DYNA and HIACE platforms, covering various body styles including cargo vans, buses, pickups, flatbed chassis, and box trucks, totaling 8 models, as detailed below:

Year Range	Brand	Series	Body Type	Chassis Code / Engine Displacement
1977 – 1984	TOYOTA	DYNA	Box (Cargo Van)	BU20 / 3.4D
1977 – 1979	TOYOTA	DYNA	Bus (Bus)	U3, U2 / 2.4D (JU20_)
1977 – 1987	TOYOTA	DYNA	Bus (Bus)	U3, U2 / 3.4D (BU82_)
1977 – 1979	TOYOTA	DYNA	Pickup (Pickup Truck)	2.4D
1977 – 1984	TOYOTA	DYNA	Platform/Chassis (Flatbed Chassis)	U, Y / 2.0 (RU20_, RU25_, RU30_)
1977 – 1979	TOYOTA	DYNA	Platform/Chassis (Flatbed Chassis)	U, Y / 2.4D
1977 – 1983	TOYOTA	HIACE I	Box (Cargo Box)	RH1_, LH3_, RH3_, RH2_, LH2_, LH1_
1977 – 1982	TOYOTA	HIACE I	Wagon (Passenger/Cargo Commuter Vehicle)	LH1_, RH1_, LH3_, RH3_, LH2_, RH2_

Product Specifications

Parameter Item	Specifications
Product Model	XUI3540A
OE Number	31410-26020 / 31420-26021 / 31420-26022 / 31420-26092 / 31420-36030 / 31420-36031 / 31420-36032
Cylinder Bore (DIA)	15.87 mm
Mounting Size	Φ27.5 / 50 / 2-Φ9 (Direct mount, no bevel)
Hydraulic Connection (Connecting Size)	M12 × 1.0
Applicable Transmission Type	Manual Transmission
Applicable Vehicle Years	1977 – 1987
Number of Vehicles Covered	8 (DYNA 6 models + HIACE I 2 models)

For commercial vehicles (trucks, buses, pickups), the clutch is used far more frequently than in ordinary passenger cars, and the master cylinder seals are more prone to wear. The clutch master cylinder is the core hydraulic component of the clutch system in manual transmission vehicles. The workflow is simple: the driver depresses the clutch pedal → the master cylinder converts the mechanical force into hydraulic pressure → hydraulic oil pushes the driven cylinder through the lines → the clutch disc disengages → the vehicle achieves smooth gear shifting.

Market Background: The first generation of Toyota DYNA and HIACE were the main commercial vehicles in Southeast Asia, the Middle East, Africa, and Oceania during the 1970s and 1980s, with extremely high export volumes. Currently, a large number of these vehicles remain active in the aforementioned market, with most being over 40 years old. As the clutch master cylinder is a high-frequency wear component, original parts are increasingly scarce, leading to a strong and continuous demand for replacement parts.

Core Functions
Hydraulic Pressure Conversion: Linearly converts pedal force into hydraulic output, ensuring precise gear shifting suitable for the frequent gear-shifting conditions of commercial vehicles.
Sealed Hydraulic Circuit: Built-in high-precision sealing components effectively prevent brake fluid leakage, ensuring long-term stable system pressure without degradation.
Original Cylinder Bore Matching: The 15.87mm cylinder bore matches the original vehicle calibration, and the hydraulic output force and pedal travel conform to the DYNA/HIACE original vehicle design.
High-Frequency Pedal Resistance: Optimized seal fatigue resistance for commercial vehicle operating scenarios (frequent stops and gear shifts), achieving a service life meeting original factory requirements.
Direct mounting with no modifications: Mounting flange size Φ27.5/50, no 45° bevel (straight hole mounting), simply align with the original vehicle mounting position for installation. M12×1.0 interface directly connects to the original vehicle's hydraulic lines.
Cross-platform universal design: The same product covers DYNA cargo boxes, buses, pickups, flatbed chassis, and HIACE vans and station wagons. A single SKU is sufficient to meet the maintenance needs of various vehicle body types.

Main Target Markets: Southeast Asia, Middle East, Africa, Oceania

What problems can this product solve for your customers?

Private Label/OBM Customers
Supports OEM/ODM branding; packaging and labeling are customized to brand requirements. Toyota DYNA/HIACE is a highly recognized commercial vehicle platform in Southeast Asia and Africa. With a private label, it enjoys natural brand recognition in local repair shops and the transportation industry.
 Covers 8 vehicle models with a single product, making it an efficient "one product, multiple uses" category in the private label SKU library. A small investment can cover a wide range of market demands.
Provides complete technical data (parameter tables, dimension drawings, ISO certification documents), supporting qualification application and brand listing.

Wholesale Distributor
Covers 8 vehicle models: DYNA cargo box, bus, pickup truck, flatbed chassis, and HIACE cargo box and station wagon. One part number manages multiple body styles, significantly simplifying SKU inventory complexity. • DYNA/HIACE first-generation vehicles are over 40 years old. Toyota original parts have long been discontinued or are in unstable supply, leading to a high market reliance on quality replacement parts. These are "classic parts" suitable for long-term, stable inventory.
Diesel versions (2.4D, 3.4D) are widely used in agriculture and transportation in Africa and Southeast Asia, resulting in high maintenance frequency and consistently strong demand for parts.
Full inspection before shipment ensures sealing performance and dimensional accuracy meet original factory requirements, effectively reducing your after-sales return rate.

Cost Optimization for Customers
Consistent with original factory specifications, offering more competitive pricing, helping you increase profit margins without compromising customer satisfaction.
ISO 9001 quality management system certification ensures traceable quality, serving as a quality demonstration to downstream dealers and importers.
Supports mixed-shipment purchasing with other Toyota commercial vehicle parts (such as DYNA 200, HIACE III, etc.), consolidating shipments to reduce per-piece logistics costs.

Q1: What is the difference between XUI3540A and Toyota original parts?
A: XUI3540A is an OEM equivalent manufactured to original equipment (OE) specifications. The cylinder bore, flange mounting dimensions, and hydraulic interface threads are identical to the original parts, conforming to ISO 9001 quality standards. Since the first generation of DYNA/HIACE original parts are discontinued or have long lead times in some markets, this product can serve as a stable alternative.

Q2: Are the master cylinders for DYNA and HIACE truly interchangeable?
A: XUI3540A covers both DYNA (BU20, JU20, BU82, RU20/25/30, etc.) and HIACE I (RH/LH series) models. During this period, they shared the same clutch master cylinder mounting structure and hydraulic interface specifications (Φ27.5/50 flange + M12×1.0 interface), thus one product can cover both platforms. We recommend confirming the chassis code or VIN before placing an order. If you have any questions, please contact us for assistance.

Q3: These vehicles are quite old, are the parts still easy to find?
A: Precisely because of their age, Toyota has gradually discontinued or reduced the supply of parts for these early models, resulting in a higher market demand for quality replacement parts. These products are considered "scarce and essential" in the existing repair markets of Africa, the Middle East, and Southeast Asia, representing a valuable entry point for dealers to differentiate themselves in the market.

Q4: Are special tools or pipe modifications required for installation?
A: No. This product uses a direct-mount design (no 45° angle). Simply align it with the original mounting holes and secure it with standard tools. The M12×1.0 hydraulic pipe interface connects directly to the original vehicle's piping, requiring no adapters or pipe modifications.