20/10/2026
The CAT 259D is listed with two track sizes, 320 x 86 x 53B (C-lug or Z-lug) and 400 x 86 x 53B (C-lug), both with an 86 mm pitch and 53 links. This guide covers how to confirm the fit, the signs of wear and the 259D sprockets, idlers and bottom rollers to check.
Looking for CAT 259D tracks? Our catalog lists the CAT 259D with two track widths and two tread patterns. This guide gives the CAT 259D track size, how to confirm the fit, the signs that tracks are worn and the 259D sprockets, idlers and bottom rollers worth checking while the tracks are off.
The short answer
Our catalog lists two track sizes for the CAT 259D. The pitch and link count are the same for both. The choices to make are the width and the tread.
| Track size | Width | Pitch | Links | Tread |
|---|---|---|---|---|
| 320 x 86 x 53B | 320 mm (12.6 in) | 86 mm | 53 | C-lug |
| 320 x 86 x 53B | 320 mm (12.6 in) | 86 mm | 53 | Z-lug |
| 400 x 86 x 53B | 400 mm (15.7 in) | 86 mm | 53 | C-lug |
Source: Excavator Parts Direct catalog, October 2026. Sold as a single track (price is per track).
Read the size as width x pitch x links. A 320 x 86 x 53B track is 320 mm wide, has 86 mm between link centers and has 53 links.
Order the width that is on the machine now. If the size is still readable on the old track, use it. If you want to change width, talk to the team first so we can check it with you. The Z-lug tread is listed in the 320 mm width only.
If the size is still readable on your old track, use it. If it has worn away, take three measurements:
Width
Measure across the track from edge to edge. A CAT 259D track should measure 320 mm (12.6 in) or 400 mm (15.7 in).
Pitch
Measure from the center of one link to the center of the next. The 259D track has an 86 mm pitch.
Links
Count the drive lugs around the inside of the track. The 259D track has 53.
If your numbers match one of the sizes in the table, you have the right track. Our guide to measuring rubber tracks shows each step with diagrams.
Confirm the model
Check the model plate on the machine. These sizes are for the machine listed in our catalog as the CAT 259D. If the plate shows a different model, contact us with the machine details and serial number and we will check.
Match the size
Compare the size on the old track, or your measurements, with the table above. If the pitch is not 86 mm or the link count is not 53, stop and check before you order.
Choose the width and tread
Keep the width the machine has now. In 320 mm, choose a C-lug or Z-lug tread; in 400 mm, the C-lug is listed. The right tread depends on the ground the machine works on most. Tell us about the work and we will help you choose.
Look underneath first
Before the new tracks go on, inspect the sprockets, idlers and bottom rollers. New tracks on a worn undercarriage wear out sooner.
Our advice
A size that is checked, not guessed, is the quickest way back to work. If anything does not match, talk to the team before you order, so you maximize machine uptime and avoid a return.
We recommend these checks on any tracked machine.
If the track keeps going slack after you adjust it, do not assume the track is the cause. A track adjuster with failed piston seals cannot hold tension, and worn sprockets can add to the problem. Here is how to check rubber track tension. The correct tension figure for the 259D is in your machine’s operator’s manual.
When sprocket teeth wear sharp, they stop holding the track cleanly. The track can slip or jump through the sprocket, and the shock load travels into the final drive. If you see or hear this happen, stop and inspect the sprockets before you carry on.
If a set of tracks wears out well before the last set did, look at the parts underneath before you fit new ones. Material packing between sprocket teeth, rollers and the track also speeds up wear, so keep the undercarriage clean. Our guide to spotting a worn sprocket shows what to look for, and these five tips to extend rubber track life cover other common causes.
Spinning the tracks, unnecessary reversing, high travel speed when it is not needed and always turning in the same direction all add wear. They wear the tracks and the sprockets that drive them.
With the tracks off, the whole undercarriage is in plain view. That makes a track change the best time to inspect it. Here is what our catalog lists for the 259D:
| Part | Per machine | Weight each |
|---|---|---|
| Drive sprocket | 2 | 16.3 kg (35.9 lb) |
| Idler | Front (triple or double flange) and rear | Not listed |
| Bottom roller | 4 | 27.8 kg (61.3 lb) |
Source: Excavator Parts Direct catalog, October 2026. Kilogram weights converted from the catalog’s pound figures.
The sprocket bolts to the final drive and its teeth engage the track to drive the machine. Our catalog lists 2 per 259D. Sprocket wear is hard to judge by eye, so compare yours with an unused sprocket of the same type. Wear builds faster in reverse and at higher travel speeds.
Idlers guide the track around each end of the track frame and work with the track adjuster to hold tension. Our catalog lists three 259D idler options: a front idler with a triple flange, a front idler with a double flange, and a rear idler. Match the position and the flange type of the idler you are taking off. With an idler off, it is also the easiest time to check or replace the track adjuster.
Bottom rollers run along the underside of the track frame and carry the machine’s weight on the track. Our catalog lists 4 per 259D. Look for flat spots, worn flanges, oil leaks and rollers that no longer turn. We advise changing bottom rollers as a set, because a single new roller sits proud of the worn ones and wears faster.
Our advice
If the sprockets, idlers or rollers show wear, replace them with the tracks. It is one job and one round of downtime, and the new tracks start on a sound undercarriage.
These are the 259D parts in our catalog. All four are on the CAT 259D parts page.
More CAT parts
Our catalog lists two track sizes for the CAT 259D: 320 x 86 x 53B and 400 x 86 x 53B. Both have an 86 mm pitch and 53 links. The difference is the width: 320 mm (12.6 in) or 400 mm (15.7 in).
Our catalog lists the CAT 259D track in two widths, 320 mm (12.6 in) and 400 mm (15.7 in). Order the width that is on the machine now, and talk to our team before you change width.
It is the track size, written width x pitch x number of links. The track is 320 mm wide, has an 86 mm pitch and has 53 links.
The 320 mm track is listed with a C-lug or Z-lug tread. The 400 mm track is listed with a C-lug tread only.
Yes. We sell CAT 259D rubber tracks individually, and the price shown is for one track.
Our catalog lists the CAT 259D idler as a front idler with a triple flange, a front idler with a double flange, or a rear idler. Match the position and the flange type of the idler you are replacing. If you are not sure, send us the serial number and a photo.
Our catalog lists 4 bottom rollers and 2 drive sprockets per machine for the CAT 259D.
Common signs are a track that will not hold tension, a track that slips or jumps on the sprocket, and tracks that wear out much faster than the last set. Check the sprockets, idlers, bottom rollers and track adjuster at the same time, because worn parts underneath shorten the life of new tracks.
Related guides
Need tracks or undercarriage parts for your CAT 259D?
Tell us your machine, its serial number and what you need. We will confirm the right parts and send a quote. Shipped across the USA.
Get a quoteTalk to the teamCAT, Caterpillar and 259D are trademarks of their owner. The make and model names are used only to identify fitment. Excavator Parts Direct parts are aftermarket replacement parts, not genuine OEM parts, and Excavator Parts Direct is not affiliated with any manufacturer named.
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