The Caterpillar 320 and 325 excavators are workhorses in the compact size class, known for their durability and versatility on job sites. Whether you use your Cat 320 or 325 for general excavation, trenching, landscape projects or utility work, parts wear is inevitable and affects performance over time. Proper maintenance and installing genuine Cat excavator parts when needed will help prolong the life of your C series excavator.

The engine is the lifeblood of any excavator. The Cat320 and C325 models come equipped with a Cat C3.4 diesel engine. Over hundreds of operating hours, engine parts like the air filters, fuel filters and oil filters will need regular changing. Engine oil should be changed every 250 hours to flush out contamination and keep the parts lubricated. Other wear parts like glow plugs, fuel injectors and injector O-rings will deteriorate and ultimately require replacement. Keeping the engine well-maintained reduces down time, prolongs component life and optimizes fuel efficiency.


A robust undercarriage system as stability and mobility

A robust undercarriage system is crucial for stability and mobility when working in challenging conditions. Look for excessive wear of the tracks and rollers which could lead to derailment or uneven movement. The tracks on Cat 320 and 325 excavators are designed for maximum durability, but still have service limits of around 1,200 to 1,800 machine hours depending on work conditions. Inspect track components such as tensioners, fasteners, idlers and bushings for proper adjustment and signs of damage. If an undercarriage part fails prematurely, consult a Cat dealer to determine if a defective part needs to be replaced under warranty.

The hydraulic system functions – boom, stick, bucket and swing

The hydraulic system operates all of the working functions of the excavator including the boom, stick, bucket and swing. Over time, hydraulic oil breaks down and accumulates contaminants which reduce efficiency. Change the hydraulic oil filter after the first 50 hours, then every 500 hours or annually. Monitor hydraulic lines and hoses for leaks, abrasion, bulging or cracking and replace as needed. The hydraulic cylinder rods and seals can also fail prematurely, resulting in less than optimal digging power. Genuine Cat hydraulic parts are manufactured to the strictest specifications to maximize pressure handling and service life.

Additionally, common wear parts for Cat 320/325 excavators include the bucket and teeth/tips, loading and attachment cylinders, control levers and cab components. The bucket experiences the most punishment and typically needs to be replaced every 1,500 to 3,000 hours depending on material types being handled. Worn bucket edges can be repaired by welding, but complete replacement may be necessary if the side plates are damaged. The bucket teeth take the initial impact of rocks and debris, so they require frequent changing to maintain digging productivity. Other recommended spare parts are brake pads, hoses, belts and filtration elements.