Maintaining Your Hitachi EX55 Excavator’s Bottom Rollers

Jun 7, 2023 | News

The bottom rollers on an Hitachi EX55 excavator are an essential but often overlooked component of the undercarriage system. Properly maintaining and replacing these rollers can significantly extend the life of other undercarriage parts like tracks and sprockets.

Function Of EX55 Bottom Rollers

EX55 bottom roller supports the weight of the excavator body and undercarriage and guide the track chains. As the tracks move, the rollers rotate to guide the chains smoothly and evenly. Bottom rollers also:

• Absorb shock from uneven ground conditions
• Reduce vibration transmitted to the cabin
• Distribute the weight of the excavator body across multiple rollers for less ground pressure

wear and tear on the EX55’s bottom rollers can cause:

• Tracked chain misalignment and improper tension
• Uneven track wear
• Increased track friction and sprocket wear
• Rough ride and higher vibration levels


Inspecting And Replacing EX55 Bottom Rollers

Regular inspections of EX55 bottom rollers should check for:

• Cracks or breaks in the rollers
• Excessive side-to-side play
• Seized or jammed bearings inside the rollers
• Excessive wear on contact surfaces with the track chains

When to replace EX55 bottom rollers:

• Roller shafts are visibly bent
• More than 1/4″ of side play develops
• Chains derail or jump tracks frequently
• Noisy operation or excess vibration occurs

Using genuine Hitachi EX55 bottom rollers is recommended for optimal performance and fit. These OEM parts are:

• Rigidly tested to meet Hitachi’s specifications
• Engineered to work with other EX55 undercarriage parts
• Made of materials specifically formulated for Hitachi excavators

Replacing worn EX55 bottom rollers can:

• Reduce track and sprocket wear
• Improve ride, shock absorption and vibration damping
• Restore proper chain alignment and tension
• Reestablish smooth chain movement and power transfer