Skip to main content
Buy Any Part Logo

Caterpillar Engine Identification Guide

Caterpillar manufactures some of the most widely used diesel engines in the world — powering not just Cat machines but also generators, marine vessels, trucks and industrial equipment. Identifying your engine correctly is essential for ordering the right service parts.

C-Series Engines (Current Range)

The C-series is Caterpillar's current engine lineup, using the C prefix followed by displacement in litres:

  • C1.1 — Displacement: 1.1L • Cylinders: 3 • Typical Applications: Mini excavators (301–302)
  • C1.7 — Displacement: 1.7L • Cylinders: 3 • Typical Applications: Compact excavators
  • C2.2 — Displacement: 2.2L • Cylinders: 4 • Typical Applications: Skid steers, compact equipment
  • C2.8 — Displacement: 2.8L • Cylinders: 4 • Typical Applications: Small excavators (305–306)
  • C3.3 — Displacement: 3.3L • Cylinders: 4 • Typical Applications: Compact wheel loaders, backhoes
  • C3.6 — Displacement: 3.6L • Cylinders: 4 • Typical Applications: Mid-size excavators, D3–D4 bulldozers
  • C4.4 — Displacement: 4.4L • Cylinders: 4 • Typical Applications: Backhoes (430–444), mid excavators (311–315)
  • C7.1 — Displacement: 7.1L • Cylinders: 6 • Typical Applications: Medium excavators (320–326), D5–D6 bulldozers, 950 loader
  • C9.3 — Displacement: 9.3L • Cylinders: 6 • Typical Applications: Large excavators (330–340), D7 bulldozer, 966–972 loaders
  • C13 — Displacement: 12.5L • Cylinders: 6 • Typical Applications: Cat 345, D8 bulldozer, 980 loader, articulated trucks
  • C15 — Displacement: 15.2L • Cylinders: 6 • Typical Applications: Cat 349–374, D9 bulldozer, 988 loader
  • C18 — Displacement: 18.1L • Cylinders: 6 • Typical Applications: Large excavators, D10 bulldozer
  • C27 — Displacement: 27.0L • Cylinders: 12 • Typical Applications: Cat 390, D11 bulldozer, 992–994 loaders
  • C32 — Displacement: 32.1L • Cylinders: 12 • Typical Applications: Mining trucks, large generators

3000-Series Engines (Legacy Range)

Older Cat machines use the 3000-series engines. Many are still in active service:

  • 3114 — Displacement: 5.9L • Cylinders: 4 • Typical Applications: Older mid-size excavators
  • 3116 — Displacement: 6.6L • Cylinders: 6 • Typical Applications: Pre-1997 medium equipment
  • 3126 — Displacement: 7.2L • Cylinders: 6 • Typical Applications: 1997–2003 trucks, buses, medium equipment
  • 3176 — Displacement: 10.3L • Cylinders: 6 • Typical Applications: Trucks, marine engines
  • 3208 — Displacement: 10.4L • Cylinders: V8 • Typical Applications: Older trucks, marine, generators
  • 3304 — Displacement: 4.75L • Cylinders: 4 • Typical Applications: Older small/medium Cat machines
  • 3306 — Displacement: 10.5L • Cylinders: 6 • Typical Applications: Widespread — excavators, dozers, loaders, generators
  • 3406 — Displacement: 14.6L • Cylinders: 6 • Typical Applications: Large machines, trucks, marine — one of the most successful diesel engines ever built
  • 3408 — Displacement: 19.5L • Cylinders: V8 • Typical Applications: Large mining equipment, marine
  • 3412 — Displacement: 27.0L • Cylinders: V12 • Typical Applications: Large mining equipment, generators
  • 3508 — Displacement: 34.5L • Cylinders: V8 • Typical Applications: Large generators, marine
  • 3512 — Displacement: 51.8L • Cylinders: V12 • Typical Applications: Power generation, marine, submarines
  • 3516 — Displacement: 69.0L • Cylinders: V16 • Typical Applications: Large power generation, marine

Finding Your Engine Model

The engine model number is stamped on the engine data plate and often cast into the valve cover or rocker cover. Look for:

  1. Engine serial number plate — bolted to the left side of the engine block
  2. Valve cover casting — raised letters (e.g. "C7.1 ACERT")
  3. Machine serial number plate — usually lists the engine model

Perkins Connection

Since acquiring Perkins Engines in 1998, many smaller Cat machines use Perkins-built engines branded as Cat. The C1.1 through C4.4 range are largely Perkins designs. Parts are interchangeable but identified under the Cat part numbering system.

Common Engine Service Parts

  • Engine oil filter: 250–500 hours
  • Fuel filter: 500 hours
  • Air filter (primary): 500–1,000 hours
  • Air filter (secondary): 1,000–2,000 hours
  • Hydraulic return filter: 500–1,000 hours
  • Coolant filter: 500–1,000 hours

Need Help?

Can't identify your Caterpillar engine? Contact us with your machine model, serial number or photos of the engine data plate — we'll identify the engine and find the right parts.

Browse All Caterpillar Parts | Model Number Guide | Parts Identification Guide