OEX BXA059 Alternator 12V 120A Bosch Style

A brand new high-output Bosch-style alternator with a 3-year passenger vehicle warranty.

Product Overview

The OEX BXA059 is a brand new 12V, 120A alternator engineered as a direct-style replacement for Bosch-unit applications. With a higher 120A output than many standard OEM alternators, it's well suited to passenger vehicles carrying increased electrical loads from accessories such as driving lights, dual battery systems, inverters, and aftermarket audio. Featuring an internal voltage regulator, quad leg mount, and IR120 pin code, it is designed to match the mounting geometry and electrical interface of the original Bosch-style unit it replaces.

Key dimensional specs include a 54mm outside diameter 5-groove pulley, M10×1.25/11 pivot and adjusting holes, and a 136mm mount centre-to-centre distance. This is a new unit — not remanufactured — and carries a 3-year warranty for passenger vehicle applications and a 1-year warranty for commercial use.

Key Specifications

• 12V system voltage
• 120A output rating — high-output for accessory-loaded vehicles
• Bosch-style replacement unit
• Internal voltage regulator (no external regulator required)
• Quad leg alternator mount configuration
• Mount centre-to-centre distance: 136mm
• Pivot hole: M10×1.25 / 11mm
• Adjusting hole: M10×1.25 / 11mm
• Pulley outside diameter: 54mm
• Pulley section: 5-groove (poly-V / serpentine belt profile)
• Pin code: IR120
• Brand new unit — not remanufactured
• Weight: 5.8 kg
• Warranty: 3 years (passenger vehicle) / 1 year (commercial)

Features & Benefits

• 120A high-output rating — Delivers substantially more charging capacity than a typical 55–80A OEM alternator, supporting vehicles fitted with dual battery systems, inverters, aftermarket lighting, winches, or audio equipment without straining the charging circuit.
• 3-year passenger vehicle warranty — One of the stronger warranty terms in the OEX alternator range, providing genuine peace of mind for passenger and light 4WD applications. Commercial applications are covered for 1 year.
• Internal voltage regulator — Self-contained regulation eliminates the need for an external regulator, keeping the installation straightforward and reducing the number of components that can fail in service.
• Brand new unit — not remanufactured — Ships with all-new internals. No worn brushes, degraded bearings, or recycled windings. The full warranty period starts from day one of installation.
• Bosch-style design — Engineered to match the mounting geometry and electrical interface of original Bosch-unit applications, minimising installation time and avoiding the need for bracket modifications or custom wiring in compatible vehicles.
• 5-groove poly-V pulley — Compatible with the multi-ribbed serpentine belt systems commonly found on modern European and late-model Asian vehicles, matching the drive system of the original Bosch-style unit without belt or tensioner changes in most applications.
• Quad leg mount with 136mm centre-to-centre — Four-point mounting provides a more rigid, vibration-resistant installation compared to twin-leg units — important for high-output alternators operating under sustained load in demanding conditions.

Technical Specs

• Part Number: BXA059
• Brand: OEX
• Type: Alternator
• Suits Unit Make: Bosch
• Voltage: 12V
• Power Rating: 120A
• Regulator Type: Internal
• Pin Code: IR120
• Mount Type: Quad Leg
• Mount Centre-to-Centre: 136mm
• Pivot Hole: M10×1.25 / 11mm
• Adjusting Hole: M10×1.25 / 11mm
• Pulley Outside Diameter: 54mm
• Pulley Section: 5-Groove
• Condition: New (not remanufactured)
• Weight: 5.8 kg
• Warranty: 3 years (passenger) / 1 year (commercial)
• Unit of Measure: Each

Compatible With / Goes Well With

• Vehicles originally fitted with Bosch-style 12V alternators matching the above mounting and electrical specifications
• Applications requiring IR120 pin code internal regulator alternators
• 5-groove poly-V / serpentine belt drive systems with 54mm pulley compatibility
• Quad-leg bracket mounting configurations with 136mm centre-to-centre spacing
• Vehicles with elevated auxiliary electrical loads — dual battery, inverter, lighting, audio, or winch systems where a higher output alternator is beneficial

Important: Compatibility must be verified against your specific vehicle make, model, engine, and build date before purchase. Cross-reference the pin code (IR120), mount dimensions (136mm C-C), pivot and adjusting holes (M10×1.25/11), and pulley OD (54mm, 5-groove) against your original unit or vehicle workshop manual. Consult a qualified auto electrician if you are unsure.

Weight

5.8 kg.

Frequently Asked Questions

Is this a new alternator or a remanufactured unit?

The BXA059 is a brand new alternator — not remanufactured. It ships with all-new internal components including windings, brushes, and bearings, and is backed by a 3-year passenger vehicle or 1-year commercial warranty.

How do I confirm this alternator will fit my vehicle?

Cross-reference the pin code (IR120), mount centre-to-centre (136mm), pivot and adjusting hole specs (M10×1.25/11), and pulley OD (54mm, 5-groove) against your original unit or vehicle workshop manual. When in doubt, consult a qualified auto electrician before ordering.

What is the warranty difference between passenger and commercial use?

The BXA059 carries a 3-year warranty when fitted to a passenger vehicle and a 1-year warranty when used in a commercial application. Retain your proof of purchase and ensure installation is correct, as improper fitment may affect warranty eligibility.

Does this alternator need an external voltage regulator?

No — the BXA059 features an internal voltage regulator, so no separate external regulator is required. Regulation is fully self-contained within the alternator body.

What belt type does the 5-groove pulley suit?

The 5-groove pulley is designed for poly-V or multi-ribbed serpentine belts, which are standard on most modern vehicles fitted with Bosch-style alternators. In compatible applications, the existing drive belt can typically be reused without modification.