Superior Tire and Rubber
Jerrod Ossa, Aftermarket Sales Manager Agricultural Components
As harvest season winds down in late November and early December, many producers will be pulling their equipment into the shop for annual maintenance. For those using RT or rubber-tracked equipment, maintaining undercarriage components is crucial. But how do you know what needs attention and what doesn’t? Let’s explore key indicators that can help you determine if your undercarriage is ready for another season or in urgent need of repairs.
Midrollers
Undercarriage inspections are usually straightforward, as most damage and wear are visually detectable. Midrollers tend to wear out faster than other components, making them a reliable starting point for an inspection. Most undercarriage systems feature rubber tread on midrollers, idlers, and drive wheels. If you see tearing or chunking in the rubber, it’s important to replace these parts promptly. Worn treads can increase friction and heat, accelerating wear on the rubber track.
High heat buildup is especially damaging to both tracks and midrollers. Over time, the repeated heating and cooling of the midrollers causes the bonding adhesive between the steel wheel and rubber to break down. If this separation begins, wheel failure is imminent, and replacement is necessary. When replacing midrollers, it’s recommended to swap them in pairs (both the inner and outer midrollers) to ensure even wear.
Rubber Track and Guide Lugs
When visually inspecting your undercarriage, don’t forget the rubber track itself. Pay special attention to the guide lugs, which can develop cracks or tears, especially around their base. Misaligned tracks can cause midrollers to wear unevenly, rubbing more aggressively against the track lug. This not only damages the track but also harms the midrollers. A telltale sign of track misalignment is heavy wear or missing material on the inner half of the wheel. If you spot this, it’s important to replace the midrollers immediately to avoid further damage to the rubber track.
Even if the outer half of the wheel appears fine, excessive heat buildup from the exposed steel can rapidly deteriorate both the guide lugs and the midroller adhesive.
Hub-Bearing Style Wheels
For equipment with hub-bearing wheels, it’s essential to inspect the bearings and seals. If a bearing seizes, slowing or preventing wheel rotation, it can lead to issues like flat spotting or bond separation. This results in excess heat buildup, which can damage the tracks. If visual inspection while the machine is idle is difficult, try having one person crawl the machine forward slowly while another observes the wheels to see if any rotate out of sync.
For a more precise inspection, use a thermal camera or laser thermometer immediately after operation. A failed bearing will be significantly hotter than the others. Additionally, keep an eye out for sloping or stretching of the bore, which indicates improper wheel tightening or a poorly seated bearing race. These issues cause wobbling, which generates heat and deforms the hub, rendering the wheel irreparable. Cracking or chipping of the bore also makes these wheels unusable.
The Role of Heat
Heat is the number one cause of undercarriage failures. Excessive heat, whether from wheels or tracks, can damage your tracked machine. While some heat buildup can be minimized through regular maintenance, proper alignment, and limiting hard maneuvering, there is a fundamental issue with the rubber wheels used on most undercarriages.
Rubber is susceptible to heat damage, dry rot, debris embedding, and UV deterioration. A simple upgrade to polyurethane wheels can significantly reduce these risks. Polyurethane, used in midrollers, idlers, and drive wheels, is resistant to chemicals, UV, dry rot, and debris embedding. They run 30% to 45% cooler than rubber wheels and have a much higher heat tolerance. While there are only a few manufacturers of polyurethane midrollers in the U.S., one also makes polyurethane idlers and drive wheels. Upgrading to polyurethane wheels can help extend the life of your rubber tracks by dissipating heat, reducing wear, and preventing debris punctures.
Final Tips
As with any equipment, staying on top of maintenance is key. Keep moving parts lubricated and always follow the manufacturer’s torque specifications.
Stay tuned to AG Track Talk for more tips on keeping your undercarriage in top shape throughout the year.
All information is provided in this blog solely to provoke thought. All deductions made from information on this site must be confirmed by Certified Ag Track Dealer before use. Ag Track Talk does not recommend anyone conduct track service work with exception of Certified Ag Track Dealer Professionals.
