Caterpillar S115

The Caterpillar S115 is a mechanical scrap shear, a stick-mounted excavator attachment rather than a self-propelled or self-powered machine. It dates to Caterpillar's late-1990s attachment lineup, cataloged alongside the larger S128 under Caterpillar’s own service documentation, with serial prefix ADY (ADY00001-UP), placing production around 1999. The S115 was built for Cat's mid-size excavator line of the era, the 318B, 320B, 322B, and 325B, in the roughly 15 to 30 tonne class. It carries no engine, no onboard hydraulic cylinder, and no electronics of its own; the jaw is closed and opened purely through an amplifying linkage driven by the host excavator's bucket cylinder. Operating weight including its mounting bracket is 1600 kg (3,530 lb), with an overall envelope of about 2600 mm (102 in) long, 1420 mm (56 in) tall, and 305 mm (12 in) wide. Jaw opening runs 340 to 420 mm (13 to 16.5 in) with a jaw depth of 460 mm (18 in), and cutting force ranges from 1750 to 3250 kN at the throat down to 920 to 1700 kN at the primary blade, the spread reflecting which carrier's cylinder is driving it.

Across the S115's production run the core mechanical layout stayed constant; the meaningful variation is in the mounting bracket, link, and pin kit, which Caterpillar tailored to each excavator model so the amplifier geometry matched that carrier's bucket cylinder stroke and force curve. The S128 sibling covers the same role on larger carriers with a bigger jaw and higher force rating, giving buyers a two-size family rather than a single universal shear. Caterpillar did not carry the S115 name forward into a direct successor; later scrap and demolition shear work moved to the fully hydraulic S3xx and S4xx series (built around dedicated onboard cylinders rather than carrier-actuated linkage), a different design philosophy rather than a straight-line replacement. In the used and parts market today the S115 remains relevant chiefly as a low-cost mechanical shear for shops running older B-series Cat excavators, where its simplicity (no hoses, no cylinder, no seals to service) is the appeal, and demand centers on pins, bushings, blades, and mounting hardware rather than any hydraulic component.

Below: full specifications, fluids & capacities, the factory service schedule, common service parts, verified fault codes, what owners discuss, attachment guidance, the complete assembly directory, and a serial-number reference. Complete parts lists with full OEM part numbers, exploded diagrams, quantities, and fitment data are available free in Heavy Parts AI.