What Are the Best CAT 320 Track Rollers for Canadian Contractors?

The tell is usually a flat spot, and it is usually found in a yard after a machine has come off a job it should have finished. A 320 that starts drumming the track at walking pace has at least one roller that has stopped turning, and the load that roller was carrying is now going into the links, the frame and the other rollers on that side. On Canadian ground the failure is rarely sudden: it starts as a weeping seal in a roller nobody looked at.

Last updated: October 5, 2026

This guide covers how to choose rollers for a 320 working Canadian ground, what actually wears them out, how to inspect a set and read what you find, and what to confirm before ordering.

Single flange or double flange

The two configurations are not interchangeable, and which one your machine takes is a property of the undercarriage rather than a preference.

Configuration	What it is for	What to check when buying
Single flange	Guides the track from one side; common on the outer positions of the frame	Flange side, running-surface width, bore and mounting pattern
Double flange	Guides the track from both sides, holding it in line through the centre of the frame	Flange spacing, running-surface diameter, whether the bearing is sealed or greasable

On these rollers the bearing arrangement matters as much as the flange: a sealed bearing keeps its lubrication for life, an unsealed one allows maintenance access and needs it. Both are legitimate; a machine working through mud, water and abrasive grit is better served by the sealed arrangement, and the specification should be stated rather than assumed.

What wears a 320 roller out in Canada

Two machines working the same hours on different ground will not need rollers at the same time, and in Canada the differences are specific.

Rock and abrasive ground - quarry and mine work, and the broken rock that comes with demolition - wears the running surface and the flanges and attacks the seals with grit. Wet ground and forestry work are about seal contamination rather than load: water and slurry get past a compromised seal and the bearing is finished long before the running surface is worn. Urban and utility work loads rollers in a different way, with continuous turning and pivoting on hard surfaces, which shows up as uneven wear across one side of the roller and points at tension or alignment rather than at the part. And winter adds a genuine hazard on its own: a roller that has taken on water and then freezes can start the day seized.

None of that changes the answer to which roller to buy - it changes the specification and the inspection interval. A machine on abrasive ground justifies a heavier build; a machine working wet ground justifies the seal being the first thing you ask about.

Inspecting a set, and reading what you find

Rollers are checked on the same walk-round as the rest of the undercarriage, and four observations cover almost everything.

Turn each roller by hand with the machine raised and the track slack enough to allow it. Any flat spot, roughness, or free play means the bearing is done, and a roller that will not turn is transferring its load into the track. Look for a weep at the seal - a streak of oil or grease on the undercarriage after the machine has stood is the earliest warning you will get, and a sealed roller cannot be re-greased in service. Check the running surface for even, shallow wear, which is normal life being used up, against deep or one-sided wear, which points at tension or alignment. Compare side to side, because the two tracks on a machine rarely wear at the same rate, and a difference between them is information about how the machine is used.

Then decide at the level of the assembly rather than the part. A roller that has failed on a side where the others have run the same hours and the same ground means the rest are close behind, and doing the job once - with the track off and the tension released - is cheaper than repeating it three times. While the track is off, inspect the sprocket teeth and the idler face, since a hooked sprocket or a worn idler will wear a new set of rollers in the same way it wore the old one.

What a roller set costs over the life of the machine

The purchase price of a set of rollers is the least interesting number in the decision, because the cost that matters is per hour worked. The arithmetic is simple enough to run with your own figures: take the price of the set plus the labour to fit it, divide by the hours you expect to get from it, and compare that figure across the options in front of you.

Work through the example with assumed numbers. A set of rollers at $1,200 with four hours of labour at $110 an hour is $1,640 installed. If the set gives 4,000 hours, that is about $0.41 per hour. Now price the alternative that saves $300 up front but lasts 3,000 hours: $1,340 installed over 3,000 hours is about $0.45 per hour - more, not less, and before anything is allowed for the extra hour of machine time. Substitute your own prices, labour rate and expected hours; the conclusion usually follows the hours figure, which is exactly why the hours you have recorded on the last set are worth more than any claim on a listing.

Then add the line the arithmetic leaves out: a roller that fails mid-job costs the day as well as the part, and on a production machine the day is larger than the set. That is the real argument for replacing a full set at the first failure rather than replacing rollers one at a time as they go.

Confirming the fitment

A 320 is a machine family rather than a single specification, and roller part numbers differ across the B, C, D and E variants. The fitment question is answered by the part number cross-referenced to your machine's model and serial number, together with the measurements of the roller you are removing: running-surface diameter and width, bore or shaft diameter, flange configuration, and the mounting pattern. Having those in writing is what makes a purchase reversible if the part arrives wrong.

It is worth ordering the surrounding parts in the same conversation. The top and bottom roller range sits alongside sprockets, idlers and link kits for the same machines, and the wider Caterpillar undercarriage range covers the rest of the assembly - which matters because a roller set ordered alone, against a sprocket that is already hooked, buys less life than the invoice suggests. Mixed fleets are worth planning the same way: a sprocket for a Kubota machine is the same kind of decision on a different badge.

What to ask for before you buy

Four items belong in writing, whichever supplier you use. The part-number cross-reference against your model and serial number. The specification as supplied: flange configuration, bearing type and seal design, and the running-surface material and finish. The warranty terms as a period plus an operating-hours cap, whichever comes first, with freight responsibility named - on a part this weight, who pays freight is the difference between a warranty and a gesture. And the stock position and lead time, because a 320 standing still costs more per day than the difference between two suppliers ever will.

This article is part of the track rollers guide, which covers how bottom rollers are confirmed, how they wear and when to replace a set.

FAQs

Are CAT 320 track rollers the same across all variants?

No. Roller part numbers differ across the 320B, C, D and E variants, so the fitment is settled by the part number cross-referenced to your machine's model and serial number, then confirmed against the measurements of the roller you are removing - not by the model name alone.

How do I know when a track roller needs replacing?

Any flat spot or roughness when you turn it by hand, free play in the bearing, or an oil or grease weep at the seal. The first two mean the roller has stopped carrying its share of the load; the third means the bearing is losing its lubrication and cannot be saved in service.

Should I replace all the rollers on one side at once?

If they have run the same hours on the same ground and one has failed, the rest are close behind, and replacing the set in one job - with the track off and tension released - is cheaper than repeating the labour. Replacing one roller is reasonable when a single part has been damaged early on an otherwise sound set.

Sealed or greasable bearings - which lasts longer?

For most Canadian working conditions, sealed: the failure mode here is contamination rather than a lack of grease, and a sealed roller keeps its lubrication for its service life. A greasable design is legitimate where the machine's maintenance regime genuinely includes the roller, but it has to actually happen.

Do I need to replace the sprocket at the same time?

Check it, and replace it if the teeth are hooked or the pitch no longer matches the track. A new set of rollers under a worn sprocket still leaves the machine with a mismatch that wears the belt - and the belt is the most expensive part of the assembly.