CAT OEM Fuel Tanks. Repair or Replace?

When reliability matters most, CPR’s fully Australian Made tanks are built to outperform and outlast standard solutions — every time.

At CPR Fabrication, we don’t just repair mining components — we manufacture them.

As part of a recent fleet rebuild project, our team was engaged to repair a Caterpillar 793D haul truck fuel tank, upon assessment the original unit suffered from severe structural fatigue, corrosion, and internal damage. Rather than risk further downtime through repeated patch repairs, we designed and manufactured a fully Australian Made OEM replacement compatible fuel tank for less than the cost of repair.

All design, fabrication, coating, and testing was carried out in-house at our Rutherford, NSW workshop.

Through years of experience in repairing and overhauling OEM fuel tanks the CPR team have compiled the following list of failure points.

Common issues include:

Fuel system over pressurisation leading to internal and external cracking and distortion
Cracking and distortion from inadequate wall thickness
Internal baffle fatigue and weld separation
Corrosion due to insufficient protective coatings
Mounting failures and torque tube stress cracking
Repeated on and off-site repairs and refurbishment, leading to a fatigued, lower strength product
Insufficient internal bracing supporting the tank walls
Insufficient welding process of externally plug welding components instead of internally and externally welding components, leading to separation and cracking.

These failures lead to downtime, safety and environmental risks, and rising maintenance costs — all of which impact productivity and machine availability. CPR Fabrication’s solution? Redesign the tank to eliminate these weaknesses completely.

CPR Fabrication’s replacement fuel tanks are purpose-built for Caterpillar Off-Highway Haul Trucks, delivering enhanced structural integrity and reduced maintenance in the harshest mining conditions. Designed as high-performance alternatives to OEM Caterpillar components, these tanks offer improved longevity and superior durability.

Our upgrades directly address common failure points in OEM assemblies:

Strengthened Wall Construction
Wall thickness has been increased across all major surfaces to resist cracking, corrosion, and long-term structural fatigue under continuous off-highway use.
Option to include a dual skin on front and rear facing walls, further increasing durability
Upgraded Torque Tube Assembly
Designed to handle torsional loading, the torque tube now features reinforced structural elements and modified weld techniques to reduce fatigue.
Upgraded torque tube gusset package to prevent cracking
Stabilised Internal Baffle System
Baffles are now thicker, internally braced, one piece, fully seam-welded on both sides and structurally enhanced to reduce over pressurisation and vibration-related wear.
Full Structural Reinforcement
Tanks include gusset packages, RHS stiffeners, and reinforced baffle supports — boosting stability and impact resistance across all faces.
Improved Mudguard Design
Rubber guards have been replaced with high-durability bolt on alternatives.
Protective Coating
Each tank is Raptor-coated sides and bottom as added protection and corrosion resistance
Site Compliance

CPR can deliver complete with site compliance features, including fuel overflow protection, safety signage, and OEM-compatible fittings.

Fleet Applications

Our engineered fuel tanks are compatible with a range of Caterpillar Off-Highway Haul Trucks, including:

CAT 793D
CAT 793C
CAT 789C
CAT 789D
CAT 793F
CAT 797F
CAT 785C

Each tank is manufactured to match or exceed OEM part specifications and includes all necessary mounting features and documentation.

We Also Refurbish Fuel Tanks

While CPR specialises in the fabrication of new OEM replacement tanks, we also offer comprehensive fuel tank refurbishment services including service exchange for CAT off-highway haul trucks.

Refurbishment is a practical option when the existing tank structure remains serviceable and offers a cost-effective pathway to extend component life — especially where availability or downtime is critical.

Our fuel tank refurbishment process includes:

Full disassembly and strip-down of all components
Removal of external coatings and rubber lining
Fully sand blast unit
Non-destructive testing (NDT) to identify cracks, corrosion, and structural fatigue
Repairs to baffles, brackets, skins, and welds, including any previously failed modifications
Replacement of damaged or corroded sections with new CNC-cut and pressed steel
Upgrade of torque tubes, mounts, and spigots with reinforcement
Application of Raptor protective coating to high-wear and corrosion-prone areas
Pressure testing to 10 psi to ensure tank integrity
Refit and reinstall of all OEM-supplied fuel system components
Final compliance check, paint, safety signage, and return-to-site logistics