Track shoe width sets ground pressure and flotation: wider shoes spread the load on soft ground, while narrow shoes suit rock and confined work. Choose the width the manufacturer approves for your model and the ground you work, because width is a flotation decision made inside a published range. On Alberta's variable ground, the same machine can need different widths for different seasons.
Related reading: for shoe types, see our track shoe types guide, and for bolt torque, see our shoe bolt torque guide.
How Shoe Width Affects Ground Pressure and Flotation
Ground pressure is machine weight divided by the shoe area in contact with the ground. Wider shoes lower ground pressure and improve flotation on soft soil, snow, and mud, while narrower shoes concentrate the load and sink.
In Alberta's soft and variable ground, the width decision is a flotation decision. The same machine on narrow shoes sinks and ruts; on wider shoes it crosses the same ground without stopping.
Calculating the Flotation You Need
Compare the machine's weight against the shoe contact area to estimate ground pressure, and check the manufacturer's approved width options for the model. The approved range is the boundary for the choice, and the calculation shows which side of the range fits the ground.
The contact area depends on both width and track length, so the calculation is per machine, not per shoe size. A quick estimate with the machine's operating weight gives the direction; the parts book gives the approved options.
The estimate is a planning number, not a lab measurement: it tells you which way the shoe choice moves the machine on soft ground. When the site question is sink or cross, the direction of the number is the answer.
Ground Pressure by the Numbers: A Working Calculation
The calculation is simple enough to run on site, and it explains why the width answer differs between machines. The example below uses representative figures — replace them with your machine's operating weight and track dimensions.
| Input | Example value | Notes |
|---|---|---|
| Machine operating weight | 8,000 kg | From the machine spec |
| Track contact length per side | 2,000 mm | From the undercarriage spec |
| Shoe width | 400 mm vs 600 mm | Two approved options |
| Ground pressure estimate | Higher on narrow, lower on wide | Compare the two options |
Wide Shoes for Swamp, Mud, and Snow
Wide shoes are the choice for soft, wet, and snowy ground. They reduce sinking, rutting, and soil disturbance, and they keep the machine working where narrow shoes get stuck.
For oil sands and mining support, wide shoes with the right grouser pattern balance flotation with the abrasive ground. The width buys flotation, and the grouser pattern buys the grip.
Narrow Shoes for Rock and Confined Work
Narrow shoes suit rock, gravel, and confined sites where access and maneuverability matter more than flotation. They also weigh less and cost less per set, and they turn with less scrub.
On hard ground, narrow shoes have no flotation penalty and wear less in turning scrub. The saving on cost and weight is real, but it disappears the day the machine is parked in soft ground.
The confined-site case is where narrow shoes earn their keep: between walls, through gates, and around utilities, the narrower shoe fits where the wider one cannot. Measure the access before choosing, because the site's tightest point is the width decision's real test.
Manufacturer Width Options by Model
Manufacturers publish approved shoe widths for each model. Choose within the range, and confirm the bolt pattern and part numbers for the width you select, because a width outside the range changes undercarriage loading.
The approved range exists for a reason: the rollers, chain, and sprocket are engineered for shoes within it. A wider shoe than approved strains the system even when it bolts on.
Approved Widths and the Parts Book: Reading the Options
The parts book for the serial number lists the approved widths and their part numbers, and each width has its own hardware. Reading the options from the book turns the width decision into a list, not a search.
The book also shows which widths were approved for the machine generation, which matters when the same model name spans several generations. The serial number picks the page, and the page picks the options.
Width, Wear, and Turning: The Trade-Offs
Wide shoes cost more, weigh more, and scrub harder in turns. Narrow shoes are cheaper and turn more freely but sink on soft ground. The trade-off is decided by the ground you work, not by the brochure.
| Trade-off | Wide shoes | Narrow shoes |
|---|---|---|
| Flotation on soft ground | Best | Weakest |
| Rock and confined access | Harder | Easier |
| Turning scrub and wear | Higher | Lower |
| Set cost and weight | Higher | Lower |
Snow, Mud, and Seasonal Ground: When the Width Answer Changes
Alberta ground changes by season: spring thaw softens the surface, summer hardens it, and winter adds snow. A machine that crosses soft ground in spring may not need the same width in summer.
The practical approach is to choose for the dominant hours and keep the seasonal second set only where the job demands it. Changing width is a parts-book decision, so the seasonal set must be confirmed the same way as the primary set.
The seasonal change is also a wear decision: a wider shoe run in spring mud avoids the sink-and-spin that burns grousers, while the same shoe run on summer rock scrubs in turns. The width that protects the machine in the wet season can cost it in the dry one, which is why the dominant-hours rule works.
Ground Pressure Limits on the Job: Site Rules and Soil Conditions
Some sites specify a maximum ground pressure, and the shoe width is the machine-side number that meets it. Check the site's rule against the machine's ground-pressure estimate before the job, because a machine that exceeds the limit on paper may be stopped at the gate.
The same calculation that guides the width choice also answers the site question. Keeping the estimate with the machine record turns the shoe choice into documented compliance rather than a site argument.
Decision Rule
- Soft, wet, or snowy ground: choose the widest approved shoe.
- Rock, gravel, or confined sites: choose a narrower approved shoe.
- Mixed sites: choose the width that covers the majority of hours.
Conclusion
Track shoe width is a flotation decision inside the manufacturer's approved range. Match the width to the dominant ground, and balance cost, wear, and turning with flotation.
Key Takeaways for Canadian Operators
- Choose wide approved shoes for soft and wet ground.
- Choose narrower approved shoes for rock and confined sites.
- Confirm the bolt pattern and part numbers for the selected width.
See the Track Shoe collection and the 1986990 track shoe for your machine.
Frequently Asked Questions
Do wider track shoes reduce ground pressure?
Yes. Wider shoes spread the machine weight over more contact area, lowering ground pressure and improving flotation on soft ground.
Can I fit wider shoes than the standard?
Only within the manufacturer's approved range for the model. Wider shoes change the undercarriage loading and must be approved.
Why are narrow shoes better on rock?
Narrow shoes have no flotation penalty on hard ground, weigh less, cost less, and scrub less in turning.