09-29-2025, 03:58 PM
The 637E Series II and Its Twin-Engine Legacy
The Caterpillar 637E Series II scraper is part of a long lineage of twin-engine motor scrapers designed for high-volume earthmoving. Introduced in the late 1980s and refined through the early 1990s, the 637E Series II features a push-pull configuration with two engines—one in the front tractor unit and one in the rear scraper unit. This design allows for exceptional traction and loading force, especially in tough soils or uphill cuts.
With a heaped capacity of over 34 cubic yards and a top speed exceeding 30 mph, the 637E was built for production grading, highway construction, and large-scale site development. Caterpillar’s twin-engine scrapers have been used in projects ranging from interstate corridors to mining reclamation zones.
Performance Advantages Over Later G Series Models
Operators who have worked with both the E Series II and the subsequent G Series often note that the E Series offers superior mechanical simplicity and reliability. While the G Series introduced electronic controls and improved cab ergonomics, the E Series retained manual systems that were easier to service in the field.
Key advantages of the 637E Series II include:
Unit History and Fleet Integration
Two units—serial numbers 7FB710 and 7FB711—were previously owned by Kiewit and operated in Texas. These machines reportedly accumulated over 10,000 hours before being listed for sale. After sitting idle for several years, they were shipped to Australia to join a fleet that included a 24B Loadrunner and a 627B.
Integrating older scrapers into an active fleet requires:
Parts Availability and Rebuild Strategy
While Caterpillar no longer produces the 637E Series II, parts remain available through:
Operational Tips for Twin-Engine Scrapers
To maximize performance:
Conclusion
The Caterpillar 637E Series II remains a formidable machine in the world of earthmoving. Its twin-engine design, mechanical reliability, and high-capacity bowl make it ideal for large-scale grading and hauling. While newer models offer electronic enhancements, the E Series continues to earn respect for its durability and simplicity. With proper restoration and skilled operation, these scrapers can still move mountains—one load at a time.
The Caterpillar 637E Series II scraper is part of a long lineage of twin-engine motor scrapers designed for high-volume earthmoving. Introduced in the late 1980s and refined through the early 1990s, the 637E Series II features a push-pull configuration with two engines—one in the front tractor unit and one in the rear scraper unit. This design allows for exceptional traction and loading force, especially in tough soils or uphill cuts.
With a heaped capacity of over 34 cubic yards and a top speed exceeding 30 mph, the 637E was built for production grading, highway construction, and large-scale site development. Caterpillar’s twin-engine scrapers have been used in projects ranging from interstate corridors to mining reclamation zones.
Performance Advantages Over Later G Series Models
Operators who have worked with both the E Series II and the subsequent G Series often note that the E Series offers superior mechanical simplicity and reliability. While the G Series introduced electronic controls and improved cab ergonomics, the E Series retained manual systems that were easier to service in the field.
Key advantages of the 637E Series II include:
- Mechanical throttle and transmission control
- Robust hydraulic systems with fewer electronic sensors
- Proven drivetrain with high torque output
- Easier field diagnostics without proprietary software
- Compatibility with older parts and rebuild kits
Unit History and Fleet Integration
Two units—serial numbers 7FB710 and 7FB711—were previously owned by Kiewit and operated in Texas. These machines reportedly accumulated over 10,000 hours before being listed for sale. After sitting idle for several years, they were shipped to Australia to join a fleet that included a 24B Loadrunner and a 627B.
Integrating older scrapers into an active fleet requires:
- Full fluid flush and filter replacement
- Inspection of hydraulic cylinders and seals
- Rebuilding transmission packs and torque converters
- Testing electrical harnesses for corrosion
- Replacing worn cutting edges and bowl liners
Parts Availability and Rebuild Strategy
While Caterpillar no longer produces the 637E Series II, parts remain available through:
- Dealer networks with legacy inventory
- Aftermarket suppliers specializing in scraper components
- Salvage yards with compatible units
- Custom fabrication for hard-to-find brackets and bushings
- Prioritize drivetrain and hydraulic systems
- Replace all seals and gaskets during teardown
- Upgrade lighting and safety systems to meet modern standards
- Install new tires or retreads rated for scraper duty
- Document all work for resale or compliance purposes
Operational Tips for Twin-Engine Scrapers
To maximize performance:
- Synchronize throttle response between front and rear engines
- Monitor coolant and oil temperatures independently
- Use push-pull loading when possible to reduce wear
- Avoid sharp turns under load to protect the hitch and frame
- Train operators on engine coordination and bowl control
Conclusion
The Caterpillar 637E Series II remains a formidable machine in the world of earthmoving. Its twin-engine design, mechanical reliability, and high-capacity bowl make it ideal for large-scale grading and hauling. While newer models offer electronic enhancements, the E Series continues to earn respect for its durability and simplicity. With proper restoration and skilled operation, these scrapers can still move mountains—one load at a time.
