While the new year is still fresh, the question of how many tire and wheel spares a fleet – large or small – has available on short notice might be a good one to re-examine.

The sheer complexity of modern, axle-specific truck tire designs, new vocational niche market tires, increasing use of higher quality retreads, and the introduction of wide single tires that will potentially replace traditional dual sets raise some new issues when it comes to on-hand replacements.

One approach is simply to answer the question: “What does it cost your customer – and, ultimately, perhaps your business relationship – not to have a replacement piece immediately available?” Or, more likely: “What costs accrue from using a ‘will fit,’ but not optimum, part?”

Such cost quantification might satisfy even the most analytic and obsessive fleet purchasing decision makers, but getting a satisfactory and workable answer can be a little tricky. The key is to include all of the significant costs, and then weigh available alternatives – all from your customer’s perspective.

When it comes to replacement part availability, most truck operators would agree that minimizing downtime should receive the highest priority. But this can vary.

For example, consider a cargo of frozen food vs. longer lead-time dry freight. Since most fleets have established a specific time-related downtime cost, this number (or a reasonable approximation) is usually accessible. In this case, the cost of the readily available replacement part(s) is likely to be the second-most important consideration.

Eliminating Surprises

Tire pricing is notoriously volume sensitive. Picking one out of a shop rack vs. buying a single unit on the road might easily result in costs to your fleet customer that vary by a factor of two. So, it’s a good idea, when negotiating with a tire supplier, to establish a low-volume pricing structure with several break points (such as at two, five or 10 tires), and limited restrictions as an addendum to major tire supply contracts.

This reduces surprises for your customer and increases the likelihood that you might serve as the preferred emergency tire supplier as well as the fleet’s primary supplier. It also reinforces the perception that you have a continuing interest in servicing the account as a sole supplier and resource.

Service cost differences might also be added into your cost and pricing analysis, and most customers understand the logic of higher costs associated with small-volume deliveries.

One factor sometimes ignored is the cost associated with using a component that is compatible, or ‘will fit,’ but not necessarily the customer’s first choice. This might result in a non-compatible casing when retread time arrives, a tire that is difficult to match in a dual set at rotation time or a tire/wheel assembly that can create a steering side pull or other handling complaints on a front-axle application.

If the end result is supplying your customer with a tire or wheel that must be removed early or reapplied to another wheel position to remain serviceable, additional costs and dissatisfaction are incurred.

Many fleets have (and all should have) established guidelines for mixing tire brands and tread types across axles and in tandem drive sets, in addition to guidelines for matching overall diameters in dual sets. These application restrictions are designed to maximize service life, eliminate any safety issues and ensure casing durability. They also determine if the replacement tire or wheel is a temporary or permanent solution.

Other Hidden Costs

Tire-related fuel economy penalties can also add hidden costs. Tread depth and tire brand are the main variables to be considered here. The use of a standard or premium tread rib tire on a trailer, tag or dolly axle is the most common misapplication.

While small in some respects, higher rolling resistance due to deep-tread, free-rolling tires continues to build as miles accumulate. That means higher fuel costs.

Another factor sometimes overlooked is the use of a new tire when a retread would be the preferred application. This holds true, of course, whether the replacement is provided from the fleet inventory or supplied by a vendor.

Some savvy fleets even require vendors (especially national account providers) to maintain agreed-upon quantities of retreads vs. new tires and a guaranteed mix of tread types and tread depths at designated service locations.

Offsetting costs (expenses) should also be factored in. Security issues, such as who is responsible for inventory maintenance, theft and damage losses, are considerations if multiple supply points and dedicated inventory are involved.

Just-in-time supplier agreements might look beneficial on paper, but if turned into ‘not-in-time’ or ‘unavailable’ problems in real life, there will be an unplanned expense. From a fleet perspective, just-in-time supply plus guaranteed availability (with a penalty, if violated) is a worthy goal and can be negotiated with some customers.

Regardless of who maintains the inventory, someone has to be responsible for ensuring that the stock turns regularly and that a FISH (first-in-still-here) inventory doesn’t add to long-term costs for you or your fleet customer.

Tires are chemical composites that are age sensitive. This is one reason why most fleet customers establish times to purge older tires (casings), first from line-haul service, and eventually, from short-haul duty.

Other Variables

Some of the major variables that affect inventory decisions include:

• Breadth and density of your customers’ traffic routes

• Geographic coverage of your supplying outlets (including negotiated alliances with other dealers when necessary)

• Complexity/different types of your customers’ tire and wheel choices

• Security considerations

• Overall availability of your customers’ preferred tires/wheels (often an issue with new products)

This is, of course, only a partial list and will vary by operation. However, addressing the inventory issue with some detail might result in cost savings for your customers as well as a more efficient process when those replacement tires are inevitably needed.

Ultimately, good inventory practices should result in more secure, long-term business relationships with valued customers.