Excavator Alternators
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203-5492 is a Caterpillar alternator reference in the WAI 12875N replacement family. WAI's official record specifies a new Denso IR/IF-style alternator rated at 12 volts and 110 amps with clockwise rotation and a two-groove 75 mm OD pulley. Published applications cover Caterpillar D3G, D4G and D5G machines using the Caterpillar 3046 5.0L diesel engine. Confirm the complete number, 12V/110A label, two-groove pulley, plug, mounting ears and machine serial range before ordering.
Send the machine model, engine model or nameplate photo so our team can confirm compatibility before shipment.
| Relationship | Reference family | Number |
|---|---|---|
| Primary Caterpillar Part Number | Official WAI 12875N replacement-reference entry | 203-5492 |
| Aftermarket Catalog Number | Official WAI product record | WAI 12875N |
| Caterpillar Cataloged Replacement Reference | Grouped separately from the primary number | 203-5492R |
| Denso Manufacturer References | Cataloged replacement references | 021080-0510 / 102211-3030 |
| Lester Industry Catalog Number | Catalog cross-reference only | 12875 |
Product fitment guide
Quickly compare the reference number and recorded machine applications. Use the original photos and the checklist before ordering.
Part identification
Formatting aliases are the same number written differently. Related assemblies and remanufactured numbers are not presented as direct interchanges.
Product summary
Before ordering
Machine fitment
4 model references
Compatibility lists identify searchable model families, not every production serial range. Confirm the original part number and machine serial number before purchase.
Quick fitment answers
Recorded compatible model references include Caterpillar Equipment: D3G / D4G / D4G LGP / D4G XL / D5G / D5G LGP, Published Engine: Caterpillar 3046, 5.0L diesel, Published Year Range: 2002-2008 depending on model, Fitment Limitation: Confirm 203-5492, 12V/110A label, two-groove pulley, plug, mounting and serial range. Confirm the complete part number and machine serial range before ordering.
Manufacturer number: 021080-0510 / 102211-3030.
Confirm voltage and rated amperage against the original alternator label. Compare mounting ears, pulley type and pulley-groove count. Check plug shape, terminal position and regulator connection. Send clear photos of the original unit and connector layout when requesting a quote.
