Extend the Life of Your Undercarriage

Thu July 30, 2020 - National Edition
Nathan Medcalf

Undercarriages have a varied lifespan depending on numerous factors, including the quality of the product and the application in which it is used, as well as the operator.
Undercarriages have a varied lifespan depending on numerous factors, including the quality of the product and the application in which it is used, as well as the operator.
Undercarriages have a varied lifespan depending on numerous factors, including the quality of the product and the application in which it is used, as well as the operator. Maintenance is crucial to extending the life of your undercarriage. It begins with regular checks of track tension and keeping the undercarriage clean and free of debris. There are a number of steps you can take as the operator, owner or fleet manager to extend the life of your undercarriage, thereby delaying undercarriage repair and/or replacement.


Undercarriages have a varied lifespan depending on numerous factors, including the quality of the product and the application in which it is used, as well as the operator. However, there are a number of steps you can take as the operator, owner or fleet manager to extend the life of your undercarriage, thereby delaying undercarriage repair and/or replacement.

Track Tension – Finding the Sweet Spot

The first thing you do to extend the life of your undercarriage is to monitor the tension in your tracks. Track tension refers to how tight the track sits on the rollers. Tracks get looser over time and appear stretched out; this is called elongation.

Elongation can cause premature undercarriage wear (as well as affect performance), so make sure to regularly check your tracks for signs of elongation. It can be part of your daily machine walkaround or be completed weekly, said Jordan Troutman, owner, Pivot Equipment Parts — a provider of aftermarket undercarriages.

"When you tighten tracks, don't tighten them as much as possible. The tracks should sag a little at the top between the two rollers. Check the machine manual of your machine to see the optimum amount of sag."

If your undercarriage is a single top roller undercarriage, relieve pressure by opening relief valve about one full turn. Stand on the track between the front idler and the track carrier roller in order to accurately see the amount of sag. Place something with a straight edge from the front idler to the track carrier roller.

At the point where the sag is the greatest, measure the distance from the tracks to the straight edge. Do the same between the sprocket and the track carrier roller.

If your undercarriage is a two-top roller undercarriage, place the straight edge on top of the tracks so it reaches the front roller and the rear roller. Then, at the midpoint between the two rollers, measure the distance between the tracks and the straight edge.

Then, check your machine's manual and compare your measurements to the numbers posted by the manufacturer. If your measurements are higher than the number posted by the manufacturer, tighten the tracks.

Limitation – Know and Respect What Your Machine Can Do

All machines have limitations. They are designed to be operated in a certain way in certain environments. If you ignore a machine's limitations or the manufacturer's recommendations for optimal operation, then you can expect excessive wear and premature component failure.

"And, it's not just willfully reckless (cowboy) operators and drive-them-into-the-ground producers that aren't respecting a machine's limitations. Sometimes, it can be just the application in which the machine is working. If you have a dozer with standard tracks and undercarriage, don't put it into an application where it will routinely work with abrasive material. Use a machine with a heavy-duty undercarriage or invest in some guarding," said Troutman.

Respecting performance limitations also means respecting component lifespan performance limitations. Pins and bushings don't last as long as other components in an undercarriage. Pins and bushings need to be checked routinely to determine when they need to be turned or replaced.

Operation – Operate it Like You Can't Buy a New One

Operating a machine well is more than just getting the job done; it's knowing the short- and long-term effects on the machine from how it is being operated. For example, sharp turns and counter rotations increase contact stress between components. Performed more slowly, a lot less damage is inflicted on the undercarriage.

Operating in reverse at high speed can really increase the wear on the machine's undercarriage if it is equipped with fixed bushings. Alternatively, if the machine's undercarriage features rotating bushings, the wear rate is significantly less due to the ability of the bushing to rotate so that its entire exterior wears more evenly.

Also, working on hills can increase the wear on components. When operating side-hill, the side of the machine facing the bottom of the hill experiences greater forces and therefore greater wear than the side of the machine facing the top of the hill. Work in such a way that both sides spend the same amount of time in the top and bottom positions. Take a similar approach when working uphill and downhill.

Maintenance – Prevent Undercarriage Failure With Proactive Maintenance

Maintenance is crucial to extending the life of your undercarriage. It begins with regular checks of track tension and keeping the undercarriage clean and free of debris.

"The frequency of cleaning required for the undercarriage varies by region and working material properties," said Troutman. "Muskeg, for example, can become difficult to remove if left in the undercarriage overnight, and tracks with debris in them will reduce undercarriage life. The material creates additional contact points, which result in higher wear rates."

It also includes checking wear of certain crucial parts (pins, bushings, rollers, idlers, and sprockets). These components need to be measured and then those measurements need to be compared to machine wear specifications.

Turn pins and bushings in order to increase their lifespan. Pins and bushings wear out in an uneven manner. Rotating them extends their life and therefore the life of your undercarriage.

By taking care of your machine's undercarriage with preventative maintenance and by operating the machine in ways that doesn't put excessive stress on components, you can extend the life of your undercarriage.