The Situation

In mining operations, large haul trucks are the backbone of material movement. These trucks are often diesel-electric with rear wheel assemblies critical to vehicle performance.

Here’s what’s at stake:

  • $250,000 USD — cost of each rear wheel assembly
  • $600,000 USD — potential replacement cost
  • 24,000 hours — expected service life of the rear wheel motor (per General Electric*)

To reach or exceed that lifespan, fluid cleanliness is essential. Fluid that does not meet the specification for contamination such as water, or wear metals like iron must be drained and replaced.

The Challenge

A mining customer's oil analysis after 500 hours on new fluid showed:

  • ISO cleanliness code of 25/23/18
  • Iron concentrations over 250 ppm

This level of contamination can lead to:

  • Premature wear
  • Short wheel motor service life
  • Increased downtime and poor vehicle availability
Contamination captured by magnetic plugs.

Clearly, a filtration strategy was needed to protect these critical and costly components.

The Solution

Donaldson recommended an off-line Kidney Loop Filtration Cart using Donaldson Blue® DBB8665 filters, delivering:

  • 7-micron filtration efficiency @ Beta 2000
  • Multilayer synthetic media designed for high efficiency, high capacity, and low pressure drop

The process:

  • A filter cart was connected to each wheel motor
  • 3 hours of kidney looping were performed during routine maintenance
Kidney Loop Cart with Donaldson Blue DBB8665 filters.

The Result

The impact of cleaner fluid was significant:

  • Fluid contamination reduced by up to five ISO codes, meeting OEM expectations
  • 4x longer fluid drain intervals, reducing oil replacement and disposal costs**
  • Up to 1.7x increase in component life (based on Noria Life Extension Table)

Regular fluid analysis is still essential, every 500 hours or per your OEM’s recommendations.

Diagram of the Wheel Motor Kidney Loop System.

Looking to protect your haul truck investments and reduce lifecycle costs?

Talk to your local Donaldson specialist today for customized off-line filtration systems that are built to keep your fleet running longer, smoother, and more efficiently.

*Reference the GE publication no. WB2790.
**Results based on two surface mining operations.