Company Background & Model Lineage
Kobelco (a brand of Kobelco Construction Machinery Co., Ltd.) has a rich history in hydraulic excavator manufacturing, beginning with Japan’s H208 crawler excavator in 1967.  Over decades, Kobelco introduced successive “Mark” series—Mark II, Mark III, Mark IV—refining hydraulics, operator comfort and machine intelligence. For its part, the SK60‑series sits in the ~6 t class of crawler excavators, suited for versatile mid‑weight applications. For example, an SK60‑III is listed at roughly 6.7 t operating weight.
Worldwide auctions show used SK60 models ranging from USD ~€7,000 to €20,000 depending on hours and spec.
Key Specifications & Features

• Operating weight: roughly 6 000 kg (≈13,200 lb) in many SK60‑class machines.
  
• Bucket capacity: ~0.24 m³ in one example sale.
  
• Engine power: for earlier SK60 models, engines ranged ~42 kW (≈56 hp) in the 1990s.
  
• Model Mark IV: includes improved hydraulic system, “computerised intelligent total control system”, automatic engine deceleration to ~1,050 rpm when idling, and dual “mechatronic digging modes” for power/speed trade‑offs.
  
• Versatility: The machine is engineered for continuous, trouble‑free operation with minimal maintenance, and targeted at applications where mid‑class performance and efficiency are key.
  

• Smaller footprint compared to larger heavy excavators, allowing better maneuverability in constrained sites.
  
• Enough hydraulic punch and bucket size to handle moderate volumes with efficiency.
  
• The dual digging modes allow operators to switch between “power” mode (for heavy digging) and “speed/eco” mode (for lighter fight work) to match job demands.
  
• Reduced idle speed and intelligent controls help save fuel and reduce operator fatigue—important in rental fleets and contractor operations focused on cost control.
  

• Check hours, service history, and whether the dual‑mode system has been maintained—look for signs of slippage, reduced hydraulic response or creeping.
  
• Inspect undercarriage: as a ~6 t machine, track wear, sprockets, rollers and links will influence remaining useful life. Undercarriage refresh can cost significant sum.
  
• Verify engine behaviour: The automatic idle drop to ~1,050 rpm is a key feature; if the idle remains high or fluctuates widely, there may be issues with control modules or sensors.
  
• Hydraulic system: Ensure the auxiliary circuits, hoses and couplers show no leaks; fluid cleanliness is critical for machines with “intelligent” hydraulic controls.
  
• Parts availability: The Mark IV still enjoys parts availability globally; one parts listing specifically supports the SK60 Mark IV model.
  

• Mid‑class excavators in the 5–8 t range remain highly in demand as rental fleets seek machines versatile enough for small‑site work yet capable of heavy tasks.
  
• Manufacturers are advancing “smart” hydraulics and operator comfort features even in this weight class, making models like the SK60 Mark IV relevant well after introduction.
  
• In regions with rising fuel costs or stricter emission controls, machines with efficient idling control and multiple digging modes are increasingly preferred, enhancing resale value.
  

• Operating Weight: The total weight of the machine including standard attachments, fuel, operator, and fluids.
  
• Digging Mode: A selectable machine setting that adjusts hydraulic pump output, engine rpm and system response to match either high‑power or high‑speed demands.
  
• Idle Speed Reduction: A feature that automatically lowers engine rpm when work is paused to save fuel and reduce noise.
  
• Undercarriage: The track system of the excavator including links, sprockets, rollers, idlers and shoes—major cost item in maintenance.
  
• Footprint: The ground‑space the machine occupies, including swing radius, track width and clearance requirements.
  

A Classic Pairing of American Truck and Two-Stroke Power
The Ford L9000 was a heavy-duty Class 8 truck produced by Ford Motor Company from the late 1970s through the 1990s. It was widely used in vocational applications such as dump trucking, lowboy hauling, and regional freight. Known for its rugged frame, spacious cab, and versatile drivetrain options, the L9000 became a staple in construction and logging fleets across North America.
One of the more iconic engine pairings for the L9000 was the Detroit Diesel 8V71, commonly referred to as the “318 Detroit” due to its 318 horsepower rating. This two-stroke V8 diesel engine was part of the legendary Detroit 71 Series, which had been in production since the 1950s and was renowned for its distinctive sound, high-revving nature, and mechanical simplicity.
The 318 Detroit Engine Characteristics
The 318 Detroit, or 8V71N, was a naturally aspirated 8-cylinder engine with a displacement of 9.3 liters. It featured:

• Two-stroke cycle operation
  
• Roots-type blower for scavenging
  
• Mechanical unit injectors
  
• High RPM capability (governed around 2,100–2,300 RPM)
  
• Dry weight of approximately 2,100 lbs
  

• Regular injector tuning
  
• Blower inspection and seal replacement
  
• Monitoring oil consumption (two-strokes tend to burn more oil)
  
• Ensuring proper cooling system function to prevent liner cavitation
  

Overview of CAV Fuel Systems
CAV, originally a British brand under Lucas, has been a major supplier of diesel injection components since the early 20th century. CAV pumps and cartridges were widely used in agricultural, construction, and industrial diesel engines, particularly in the 1960s–1990s. Traditional CAV cartridge systems required disassembly for filter changes, a process that was time-consuming and prone to contamination. To improve efficiency and maintenance, many operators have converted older cartridge-style systems to spin-on filters, which allow quick replacement without exposing the system to dirt.
Purpose of Spin-On Conversion
The conversion from a traditional cartridge to a spin-on filter provides several advantages:

• Reduced maintenance time due to quick filter replacement.
  
• Lower risk of contamination during servicing.
  
• Improved availability of replacement filters, since spin-on types are widely stocked.
  
• Enhanced filtration efficiency if modern spin-on filters with higher micron ratings are used.
  

• Adapter Installation: A spin-on adapter is mounted where the original cartridge housing was located. It must be compatible with the pump and properly sealed to prevent leaks.
  
• Filter Selection: Operators typically choose spin-on filters rated for diesel fuel, often 10–30 microns for primary filtration. The filter must handle engine flow rates and pressure.
  
• System Testing: After installation, the fuel system is bled to remove air and ensure proper flow. Checking for leaks under normal operating pressure is essential.
  
• Maintenance Schedule Adjustment: Spin-on filters often allow longer service intervals depending on fuel quality and usage.
  

• Compatibility: Not all spin-on adapters fit every CAV pump model. Proper sizing is crucial to prevent bypassing fuel or introducing leaks.
  
• Flow Restriction: Some spin-on filters can slightly restrict flow, potentially reducing fuel delivery at high loads. Selecting a filter with sufficient flow rating is essential.
  
• Seal Integrity: Improper sealing or using incorrect gasket materials can lead to leaks or air ingress, causing engine performance issues.
  

• Inspect the adapter and spin-on seal at each filter change.
  
• Use fuel-grade spin-on filters with micron ratings compatible with original specifications.
  
• Keep spare filters on hand to minimize downtime.
  
• Monitor engine performance after conversion to detect any unusual pressure drops or air ingress.
  

• CAV Cartridge: Original filter element designed for CAV diesel injection systems.
  
• Spin-On Filter: Self-contained filter unit that screws onto an adapter for easy replacement.
  
• Micron Rating: Measurement of the filter’s particle retention capability.
  
• Fuel Bleeding: Removal of air from the fuel system to maintain proper operation.
  

The Legacy of the Case 580E
The Case 580E backhoe loader, introduced in the early 1980s, was part of Case’s renowned 580 series that revolutionized the compact construction equipment market. Known for its reliability, mechanical simplicity, and ease of service, the 580E became a staple on job sites across North America. Powered by a naturally aspirated diesel engine and equipped with a mechanical shuttle transmission, the 580E offered solid performance for digging, trenching, and material handling.
One of the often-overlooked maintenance tasks on this machine is servicing the transaxle—a critical component that houses the differential and final drive gears. Proper lubrication ensures smooth power transfer and longevity of internal components.
Locating the Drain and Filler Points
On the 580E, the transaxle is integrated into the rear axle housing. The drain plug is typically located at the bottom center of the differential housing, accessible from beneath the machine. It may be recessed or protected by a skid plate, depending on configuration.
The filler port is less obvious. It is often accessed through the dipstick tube, which doubles as the fill point. This tube is located on the right side of the machine, near the operator platform. Some units may also have a dedicated fill plug on the top of the differential housing, but this varies by serial number and production year.
Before draining, always clean the area around the plugs to prevent contamination. Use a new crush washer on the drain plug during reinstallation to prevent leaks.
Recommended Oil Type and Capacity
The transaxle requires 85W-90 gear oil, a high-viscosity lubricant designed to protect hypoid gears under heavy load. This oil provides excellent film strength and resists shear breakdown, making it ideal for the torque demands of a backhoe loader.
Key specifications:

• Viscosity: SAE 85W-90
  
• API rating: GL-5
  
• Capacity: Approximately 3.5 to 4 gallons (13–15 liters), depending on axle configuration
  

• Look for metal shavings or discoloration in drained oil
  
• Check for leaks around axle seals and drain plug
  
• Inspect breather cap for clogging, which can cause pressure buildup
  

Overview of Travel Motors
Travel motors, also called final drive motors, are hydraulic components that drive the tracks of excavators and other tracked machinery. They convert hydraulic energy into rotational motion, allowing the machine to move over uneven terrain. Travel motors are essential for maneuverability, especially on medium to heavy excavators where reliability under high load is critical. Leading manufacturers like Komatsu, Caterpillar, Volvo, and Hitachi have refined travel motor designs over decades, improving efficiency, sealing systems, and torque output.
Common Issues
Excavator travel motors can exhibit various problems due to wear, contamination, or hydraulic system issues. Frequent symptoms include:

• Reduced travel speed
  
• Jerky or uneven track movement
  
• Excessive noise or vibration
  
• Hydraulic fluid leaks
  
• Complete failure to move
  

• Contaminated Hydraulic Fluid: Particles, water, or metal shavings can damage internal gears and bearings.
  
• Overheating: High ambient temperatures or overworked systems degrade seals and lubricants.
  
• Wear and Tear: Continuous heavy loads gradually erode internal components such as pistons, gears, and bearings.
  
• Pressure Issues: Incorrect system pressure or flow can prevent the motor from achieving full torque.
  
• Seal Failure: Aging or damaged seals can allow fluid bypass, reducing efficiency and causing leaks.
  

1. Visual Inspection: Look for leaks, damaged hoses, or loose fittings.
   
2. Hydraulic Testing: Measure flow and pressure at the motor to ensure proper hydraulic supply.
   
3. Noise Analysis: Abnormal sounds can indicate internal gear damage or bearing failure.
   
4. Track Performance Test: Monitor acceleration, deceleration, and track responsiveness under load.
   
5. Fluid Analysis: Check hydraulic fluid for contamination and viscosity changes.
   

• Seal Replacement: Common for minor leaks and restored efficiency.
  
• Bearing or Gear Replacement: Necessary if internal wear is detected.
  
• Motor Rebuild: Often more cost-effective than full replacement for mid-sized excavators.
  
• Hydraulic System Maintenance: Replace filters, flush contaminated fluid, and verify pressure settings.
  
• Preventive Measures: Maintain recommended service intervals, avoid overloading, and monitor fluid condition.
  

• Travel Motor / Final Drive: Hydraulic motor driving the tracks of a tracked vehicle.
  
• Torque: Rotational force generated by the motor, critical for moving heavy loads.
  
• Piston Shoes: Components in axial-piston motors that transmit hydraulic force to the rotor.
  
• Hydraulic Contamination: Presence of particles or fluids that impair motor performance.
  
• Seals: Components that prevent hydraulic fluid from leaking and maintain internal pressure.
  

The Consignment Dilemma for Heavy Trucks
Selling a used Class 8 dump truck through consignment can be a strategic move for owners who want professional representation without the hassle of direct sales. However, finding a trustworthy dealer in the western United States—especially one familiar with heavy-duty vocational trucks like a Kenworth T800—is not straightforward. Many dealers focus on new inventory and shy away from older, specialized units, leaving sellers to navigate a fragmented market.
A 2007 Kenworth T800 with a freshly rebuilt CAT engine and OEM dump truck specs presents a unique opportunity. Yet, despite its upgrades—double frame, Hendrickson suspension, high-lift gate, automatic tarp, and more—many dealers hesitate to consign such units due to age, niche configuration, and perceived market risk.
Why Dealers Often Decline Older Dump Trucks

• New truck focus: Most branded dealers (Freightliner, Peterbilt, Volvo) prioritize selling new inventory and trade-ins under warranty.
  
• Limited buyer pool: Class 8 dump trucks are highly specialized, and dealers may lack the network to market them effectively.
  
• Liability concerns: Older trucks can carry hidden mechanical risks, making dealers cautious about representing them.
  
• Space and turnover pressure: Dealers prefer fast-moving inventory. A 2007 dump truck may sit for months, tying up lot space.
  

• Online marketplaces: Facebook Marketplace and Craigslist offer direct access to buyers but require vigilance against scams and tire kickers.
  
• Auction houses: Purple Wave and Ritchie Bros. provide structured consignment with national reach. While prices may be lower than private sale, sellers avoid negotiation headaches and benefit from transparent bidding.
  
• Regional classifieds: Local platforms can attract serious buyers, especially in areas with high construction demand like Dallas or Phoenix.
  

• $45,000: Perceived as a distressed sale, may attract lowball offers
  
• $68,000: Reasonable for a clean, ready-to-work unit
  
• $85,000–$95,000: Reflects premium features and condition, but may deter quick buyers
  
• $95,000–$120,000: Comparable to dealer pricing, but unlikely to sell fast without brand backing
  

• Target multi-branch dealers: Look for businesses with locations across states and affiliations with major brands. While they may not advertise consignment, some offer it selectively.
  
• Vet auction platforms: Purple Wave and Ritchie Bros. have proven track records for vocational trucks. Review past sale prices to set expectations.
  
• Prepare documentation: Maintenance records, upgrade receipts, and spec sheets build buyer confidence and justify asking price.
  
• List on multiple platforms: Combine consignment with online listings to maximize exposure.
  

Company Background and Model Overview
The GMC brand, part of General Motors, produced the C/K Series of medium‑duty trucks through the 1970s. The C65 model belongs to the Series 65 class, which for that era was rated for gross vehicle weight (GVW) roughly between 21,000 to 40,500 lbs and gross combination weights (GCW) up to approx. 60,000 lbs for certain tandem‑rear‑axle models.  In 1976 a GMC C65 with tandem rear axles was built for applications like grain trucks, dump trucks or equipment haulers. It was designed to meet the demands of heavier loads while retaining maneuverability for farm or municipal uses.
Key Specifications
Based on typical data for this model class:

• GVW: Up to ~40,500 lbs for the Series 65 with twin rear axles.
  
• Engine options: The model could be fitted with various powerplants including V8 gasoline or diesel units; an auction example of a 1976 C65 tandem‑axle grain truck listed a 427 cu in (≈7.0 L) V8 gasoline engine.
  
• Axle configuration: Tandem rear axles allowed higher payload and better load distribution; tire size example for a grain truck version: 10.00R20.
  
• Transmission: A 5+2 speed (i.e., 5 forward plus 2 range or auxiliary gears) manual transmission was noted in field listing.
  

• Engine condition: Because gasoline engines of that era (e.g., 427 cu in) often required high maintenance, checking compression and maintenance history is vital.
  
• Transmission and clutch: A manual with many gears demands good clutch condition and linkage adjustment.
  
• Tandem axle setup: Inspect for proper axle alignment, differential maintenance, and ensure tires on both rears have matched mileage to avoid uneven loading.
  
• Frame and bodywork: After decades of service, frame structural checks (especially near suspension points) are important for safety and longevity.
  
• Brake system: Many trucks from the 1970s may still have hydraulic or early air‑brake systems; ensuring components meet current regulatory and service standards is critical.
  

• Condition (engine, body, frame) matters heavily.
  
• Original engine, transmission, and documented history increase value.
  
• Use‑case (farm, restoration, show) will determine how much investment makes sense.
  

• GVW (Gross Vehicle Weight): Total weight of the truck plus cargo and fuel.
  
• GCW (Gross Combination Weight): Total weight of the truck, cargo, trailer(s), and whatever is being pulled.
  
• Tandem Axle: Two or more rear axles mounted close together under the truck to improve load capacity.
  
• 5+2 Speed Transmission: A manual transmission offering five forward gears plus two range gears or auxiliary gears (often high/low) for heavy load operations.
  
• 10.00R20 Tire: A common heavy‑truck tire size used on medium‑duty trucks for 1970s era equipment.
  

The Genie S-45 and Its Control System
The Genie S-45 is a telescopic boom lift designed for aerial work in construction, maintenance, and industrial applications. Manufactured by Genie Industries, a subsidiary of Terex Corporation, the S-45 offers a working height of 51 feet and horizontal outreach of 36 feet. It is powered by a diesel engine and features a dual control system—one at the ground level and another at the platform—connected through a CAN-based communication network. The machine uses the ALC 500 control module to manage inputs, outputs, and safety interlocks.
Symptoms of the Intermittent Glitch
A recurring issue with some Genie S-45 units, particularly those manufactured around 2007, involves all boom and drive functions suddenly ceasing while the engine continues to run. The failure is unpredictable: the machine may operate normally for an hour or just a few minutes before losing all hydraulic functions. Restarting the engine temporarily restores operation, but the problem inevitably returns.
This type of failure suggests an electrical or logic-level fault rather than a mechanical or hydraulic issue. Since the engine remains running, the issue is isolated to the control system governing movement and lift functions.
Primary Suspects and Diagnostic Path
Several components and systems should be investigated when troubleshooting this issue:

• Emergency stop (E-stop) switches: Both the platform and ground E-stop buttons should be checked for proper contact and continuity. A worn or oxidized contact can intermittently break the circuit, disabling all functions.
  
• ALC 500 control board: This module monitors all inputs and outputs. When a fault occurs, it typically logs a diagnostic code. The LED lights on the board will flash in a pattern that corresponds to a specific error. The code chart is usually printed inside the control box lid.
  
• Voltage fluctuations: Measure input and output voltages at the E-stop contact blocks during operation and when the fault occurs. A drop in voltage or erratic readings may indicate a failing contact or corroded wiring.
  
• CAN bus communication: Intermittent faults can also stem from poor connections in the CAN wiring harness. Loose pins, moisture intrusion, or damaged insulation can disrupt communication between the platform and ground modules.
  

1. Inspect and clean all E-stop switches and connectors.
   
2. Observe the ALC 500 board for flashing diagnostic codes during a fault.
   
3. Use a multimeter to monitor voltage at the E-stop circuits and control relays.
   
4. Wiggle-test wiring harnesses while the machine is running to identify loose or broken wires.
   
5. Check for corrosion or wear at the platform control box connectors.
   
6. If possible, swap the ALC 500 board with a known good unit to isolate the fault.
   

Company Background
Hudson Brothers Trailer Mfg., Inc. was established in 1970 and is based in Indian Trail, North Carolina.  The company specializes in building heavy‑duty flatbed and deck‑over trailers for hauling equipment and material, with its “Pro Series” line rated for 10‑ton (and higher) loads. For over 50 years the brand has built a reputation for robustness, with many users citing exceptional durability when hauling heavy equipment.
Key Specifications of a 10‑Ton Model
Typical spec sheet for a 10‑ton model (for example the HTD18D or HGN10) includes:

• GVWR (Gross Vehicle Weight Rating): ~25,700‑26,700 lbs.
  
• Empty (dry) trailer weight: ~5,700 lbs.
  
• Payload capacity: ~20,000 lbs (if hitch load is kept within spec)
  
• Deck width: ~102″ (8′6″) with various deck lengths depending on model.
  
• Axles: typically two 10k‑lb (10,000 lb) oil‑bath Dexter axles with brakes.
  
• Construction: heavy‑channel main frame (for example 10″ channel @ ~15.3 lb/ft on one model) plus reinforced cross‑members.
  

• Hitch load / tongue weight: A heavy load shifts weight onto the truck hitch; excessive hitch/axle load can exceed truck or trailer limits.
  
• Tire & rim ratings: A trailer may have an axle rating, but if tire/wheel assembly is undersized, then risk of failure (e.g., blow‑out) under heavy load increases.
  
• Brake system: On heavier loads, brakes become critical. Trailer buyer reports stress that “keep your brakes well adjusted & inspected” when near or above nominal ratings.
  
• Legal compliance: Even if physical capacity exists, hauling more than rated without proper permits, or exceeding state weight/axle limits, may result in fines or safety citations.
  
• Frame and structure: Many users of older Hudson trailers reported rugged design and long service life, but warned that modifications (e.g., to increase capacity) require structural inspection.
  

• Always check the GVWR of the trailer and subtract the trailer’s own weight to determine the usable payload.
  
• Inspect the trailer’s axle rating, tire & rim capacity, and brake system condition—especially if you plan to approach or exceed standard payload.
  
• If hauling heavy equipment (20,000 lbs+), ensure hitch/load distribution is correct to avoid overloading truck or trailer hitch.
  
• For frequent heavy hauling, consider a trailer rated above your maximum load to preserve safety margins and reduce wear.
  
• Maintain service records: bearing lubrication, brake adjustment, structural weld checks, and tire condition—especially for trailers in constant use.
  
• Understand local and state laws regarding overweight or oversize loads: even if equipment seems physically able, you may need permits or escorts.
  

• GVWR (Gross Vehicle Weight Rating): Maximum allowable total weight of the trailer plus its loaded cargo.
  
• Payload Capacity: GVWR minus the empty weight of the trailer (and minus the hitch load, if relevant).
  
• Axle Rating: Maximum load that an axle (including its wheels and tires) is designed to carry safely.
  
• Tongue/Hitch Load: The portion of the trailer load transferred to the towing vehicle’s hitch or drawbar.
  
• Deck‑Over Trailer: A trailer design where the deck is positioned over the trailer axles, providing a low load angle and easier equipment drive‑on.
  

The D5G’s Role in the Mid-Size Dozer Market
The Caterpillar D5G, introduced in the early 2000s, was designed as a versatile mid-size crawler dozer for grading, site prep, and light to moderate earthmoving. Powered by a CAT 3046 diesel engine producing around 99 horsepower, the D5G featured hydrostatic drive, a fully enclosed cab option, and a compact footprint ideal for both construction and forestry applications. Its popularity stemmed from its balance of power and maneuverability, making it a favorite among contractors and landowners alike.
Recurring Fan Belt Failures and Initial Observations
A common issue reported with the 2002 D5G is the repeated loss or shredding of fan belts. Operators have noted that belts are ejected or damaged during operation, often without any obvious signs of misalignment or pulley damage. This issue can lead to overheating, loss of alternator function, and eventual engine shutdown if not addressed promptly.
In one case, a D5G began throwing belts unexpectedly. Visual inspection revealed no immediate mechanical faults—pulleys appeared aligned, and bearings seemed intact. However, the problem persisted even after replacing the belts.
Diagnosing the Root Causes
Several potential causes were identified through systematic troubleshooting:

• Belt tensioner malfunction: A common culprit in belt failures. If the tensioner seizes intermittently due to bearing wear or heat expansion, it can cause the belt to slip or shred. This issue is often intermittent, making it difficult to detect during idle inspection.
  
• Crankshaft harmonic balancer failure: A less obvious but critical component. If the balancer deteriorates internally, it can introduce vibration and misalignment, leading to belt instability. In one documented case, replacing the balancer resolved persistent belt ejection after all other components had been checked.
  
• Mismatched belt pairs: The D5G uses dual belts for the fan and accessory drive. If the belts are not a matched set—meaning they differ slightly in length or tension characteristics—one belt may carry more load, leading to premature failure. This was ultimately identified as the root cause in a specific instance where one belt consistently jumped off while the other remained intact.
  

• Always install a matched pair of belts from the same manufacturer and batch
  
• Inspect and, if necessary, replace the tensioner and idler pulleys
  
• Check for any signs of oil contamination or glazing on pulleys
  
• Use a belt tension gauge to verify proper installation tension
  
• After initial operation, recheck belt tension and alignment
  

• Inspect belts every 250 hours or monthly, whichever comes first
  
• Replace belts every 1,000 hours or annually, even if no visible wear is present
  
• Monitor for squealing, fraying, or belt dust near pulleys
  
• Keep spare matched belts on hand, especially for remote job sites