Mining tyre TCO: a model you can apply

Most fleets answer "what does a tyre cost?" with the invoice price. That number is real, but it is

not a cost — it is a purchase. The cost only exists once you divide it by what the tyre actually

delivered, and that is where the numbers get uncomfortable.

This article gives you the arithmetic. The inputs are yours; the structure is the part worth

borrowing.

The wrong denominator

Comparing tyres by purchase price assumes every tyre delivers the same hours. On a mine site that

assumption fails constantly: one tyre completes its planned life, the next is pulled at 60% because

it ran soft, a third is destroyed by a cut. All three were invoiced for the same amount. Only one

of them earned it back.

So the denominator has to be hours delivered, not tyres bought:

> Cost per machine-hour = (tyres consumed in the period) ÷ (machine-hours in the period)

Everything below is an attempt to make the numerator honest.

The five components

Split the numerator into five lines, because they are managed by different people and only two of

them respond to monitoring:

1. Planned consumption. Tyres that reach their planned hours. This is a scheduling and rotation

question; monitoring does not reduce it, and no vendor should claim it does.

2. Premature removal for wear. Tyres pulled early because of irregular wear, misalignment,

mismatched duals. Partly preventable — monitoring catches the pressure and temperature

conditions that cause it.

3. Failure events. Cuts, impacts, sidewall damage. Monitoring does not prevent the impact, but

it changes the consequence when the operator is warned in time to stop.

4. Labour for inspection. Walk-arounds, gauge checks, depot inspections. This is the line that

most often pays for a monitoring system on its own, because it is a recurring cost that

disappears when the data arrives by itself.

5. Downtime. The hours the machine did not work because of a tyre event. This is usually the

biggest line and the one finance never attributes to tyres.

A worked structure (with illustrative numbers)

The numbers below are illustrative, not market prices — substitute your own. What matters is

the shape of the result.

Assume one haul truck, one billing period:

Now express the outcome two ways. First, tyres per machine-hour: 4 ÷ 500 = 0.008 tyres/h.

Second, the share of consumption that was not planned: 2 ÷ 4 = 50%.

That second number is the one to manage. A fleet that halves premature removals has, in this

illustration, removed a quarter of its tyre consumption without negotiating a single price.

Which lever actually dominates

Before buying anything, rank the five lines for your site. In most hauls the ranking looks like

this, and it is rarely the ranking people expect:

• Downtime usually dominates, and is invisible in the tyre budget because it is booked against

the machine.

• Premature removal is second, and it is the one monitoring addresses most directly.
• Inspection labour is third, and it is the cleanest to demonstrate — hours removed from the

schedule.

• Planned consumption and failure events are the smallest *controllable* lines.

If your ranking puts purchase price first, you are comparing invoices, not costs.

What monitoring changes, and what it does not

A pressure and temperature system does five things worth paying for:

• It tells you a tyre is going down while the machine is still moving, not at the next

walk-around.

• It catches temperature anomalies, which often precede a bearing or brake failure that costs

far more than the tyre.

• It makes the pressure history auditable, so a wear claim against a supplier or a driver

behaviour dispute has data behind it.

• It removes part of the inspection labour line.
• It shortens the time to decision, which is the only way downtime is actually reduced.

It does not fix alignment, driver behaviour or road maintenance, and no honest supplier should

tell you otherwise. On a site where tyres fail mainly from cuts, a monitoring system will not move

the number much — and that is worth knowing before the purchase order, not after.

How to run the trial without fooling yourself

• Pick a control group. Same haul cycle, same shift pattern, no monitoring. Without this the

result is an anecdote.

• Record the same five lines for both groups, for one full billing period.
• Pre-commit to the metric. Cost per machine-hour, and the rate of premature removals. Write

both down before the trial starts.

• Do not change two things at once. If you also change the rotation schedule mid-trial, you have

measured nothing.

• One tyre life is the honest horizon. A first directional read after one period is legitimate;

a claim of payback in three weeks is not.

• Write down the baseline before anything is installed. The most common way a fleet loses money

on monitoring is not a bad product: it is starting without a baseline, so nobody can tell whether

anything improved six months later. Two numbers are enough — premature removals per hundred

machine-hours, and inspection hours per machine per week. Both come out of records the site

already keeps.

Where to go next

The specification side of this — accuracy, interval, wheel count — is on

the pressure accuracy page. The machine class and typical

configuration are on the mining TPMS page and

the mining truck installation page.

If you want to run this model on your own fleet, send the five lines with your numbers and we will

do the arithmetic in writing — including the case where the answer is "not worth it".

Send the numbers.

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