Finding opportunities to reduce maintenance and increase productivity on 40,000-lb tandem axles is critical for any successful fleet, and the right combination of winning features can propel fleets to the next level of maintainability and reliability.
Compared to other axle components, the breather can be easily overlooked, but it is essential for preventing the entry of harmful contaminants to the interior of the axle and extending lubricant life, say officials at Dana, a world-leading supplier of driveline, sealing and thermal-management technologies that improve the efficiency and performance of passenger, commercial and off-highway vehicles with both conventional and alternative-energy powertrains (www.dana.com).
Advanced breather designs, such as the patented U-tube breather standard on every Dana Spicer 40,000-lb tandem axle, performs these basic functions while also expelling air and moisture from inside the axle, they note. This prevents pressure build-up and ultimately reduces seal failures.
It is well understood that selecting the right lubrication and following regular drain intervals is important, but to ensure the longevity and performance of axles it is equally important to get lubrication to crucial internal components at the right time.
Advanced tandem axles feature a flow-through lubrication system for the inter-axle differential, the Dana officials note. "Usually available as a fleet option, a high-efficiency, on-demand lubrication pump reduces spinout and pumps lube only when required. This pump provides the added benefit of eliminating external filters, costs to replace and the headache of disposing them.
"To optimize the lubrication system, premium input and output seals further extend axle life and reduce maintenance," they add.
The serviceability of the axle extends all the way to the wheel hub, where the appropriate system can minimize wheel bearing adjustment, extend seal life and lower life cycle costs.
The Dana officials recommend looking for best-in-class seal technology with improved, precision-manufactured bearing spacers and special-tolerance bearings that minimize the likelihood of costly brake replacements and downtime. These spacers also offer improved clamp retention and better oil flow to the bearings in dual or wide base single tire applications.
When maintenance is required, innovations designed into wheel ends, such as the Spicer LMSi Wheel Hub System, make it simpler and quicker to get the job done thanks to integrated features that control bearing adjustments and eliminate installation variables, they say.
"Perhaps the best way to have confidence in the low-maintenance features of an axle is the backing of the manufacturer," say the officials. "Top of the line axles offer a comprehensive five-year/750,000 mile standard line-haul warranty; a 500,000-mile initial lube drain interval; and a 500,000-mile service interval for wheel ends."
It is important to keep in mind that the use of low-maintenance or no-maintenance components does not eliminate the need for inspections, stress the officials. Components subjected to frequent high loads, as well as those with high numbers of cycles that contain wearable materials in moving or rotating joints, need to be periodically inspected.
"The fact that components require less lubrication or last significantly longer will not guarantee infinite life or eliminate the potential for failure," they observe. "However, by meticulously evaluating all the areas that present the greatest maintenance concerns and making an informed decision when spec'ing axles, you can be sure that your axles will meet and exceed their expected service life and efficiently perform every time."