How to Measure Rubber Tracks

Rubber track size is written as three numbers separated by "x" — width in millimeters, pitch in millimeters, and link (or block) count, such as 320x86x49. Measure the old track (or the machine's drive sprocket and idlers) rather than guessing from the machine model, since the same model can ship with different track sizes depending on undercarriage options.

What the three numbers mean

The first number is track width in millimeters, measured straight across the outside of the track. The second number is pitch — the center-to-center distance between two consecutive drive lugs on the inside of the track, which has to match the tooth spacing on the drive sprocket. The third number is the link count (also called block count), the total number of lugs around the entire loop. All three have to match for a track to fit; a track that's the right width but wrong pitch or link count will not seat on the undercarriage correctly.

How to measure width

Lay the track flat or measure it on the machine, running a tape measure straight across the outer rubber surface, perpendicular to the direction of travel. Round to the nearest 10mm — track widths are manufactured in standard increments (180, 230, 260, 300, 320, 350, 400mm, and so on), so a measurement of 318mm almost certainly means a 320mm track.

How to measure pitch

Pitch is measured on the inside of the track, center to center between two adjacent drive lugs (the raised ribs the sprocket teeth engage). This is the hardest of the three numbers to eyeball accurately — a small error here can point you to the wrong track entirely, since pitch has to match the sprocket exactly for proper engagement. If you can't get a clean measurement, count the total number of drive lugs and divide the overall inside circumference by that count, then cross-check the result against your existing track's part number or the size stamped on the old track sidewall.

How to count links

Count every lug around the entire loop, not just on one side. On many tracks the link count is stamped or molded into the rubber near the size designation — check the sidewall before you start counting by hand. If the track is still on the machine and mostly intact, count around the full loop once to confirm; a partial count and doubling it can introduce errors on tracks with an odd link count.

Reading a track size chart

Manufacturer and supplier size charts list tracks by the same width-pitch-link format, usually grouped by machine make and model. When you find your measured dimensions on a chart, treat the model listing as a starting point, not a guarantee — always confirm against your actual measurements or your machine's OEM part number, since aftermarket undercarriage swaps and running-gear variants mean two machines with the same model name can take different track sizes.

Where to find the size without removing the track

Check three places before pulling anything apart: the sidewall of the existing track (most manufacturers mold the size into the rubber), the machine's parts manual or operator's manual, and the undercarriage or sprocket housing, which sometimes carries a stamped part number. Your dealer or the OEM parts department can also cross-reference a machine's serial number to the correct track size if none of those are legible.

Why matching all three numbers matters

A track that's close but not exact can still mount, at least at first — which is why mismatched pitch is a common mistake. A track with the wrong pitch will not seat evenly on the sprocket teeth, leading to accelerated wear, popping or jumping under load, and increased risk of derailment. Confirm width, pitch, and link count all match before ordering; if any one number is uncertain, verify it against the physical machine rather than a size chart alone.