Stock a Part on the Truck or Order It Per Job: Decision Tree
Why this matters
Every part you handle lives in one of three places: on the truck, on a shelf at the shop, or nowhere until you order it for a specific job. Put a part in the wrong place and you pay for it either way. Carry a rare part on every truck and you have frozen a slot across the whole fleet for a job that comes once a year. Order a common part per job and you have turned a routine call into two trips and a wait. This is a placement decision, made one part at a time, and the common parts are where most of the money is won or lost.
Start here: is the part predictable and job-critical?
Two facts decide most items before you reach the table: how predictably you need the part, and what it costs you to not have it in hand.
- If you reach for it often and running out stalls the job, it belongs close, on the truck. Stop here for that part.
- If you reach for it rarely but can predict when (it is job-specific, or tied to a call type you schedule ahead), it belongs nowhere until that job is booked. Order it per job.
- If it falls between, used sometimes, or common but bulky or expensive, it is a shop-stock candidate. Keep reading.
The three tiers
| Tier | What lives here | You pay in | You are protected from |
|---|---|---|---|
| Truck stock | Frequent, job-critical, small | Fleet-wide slots, restock effort | Stockouts on your bread-and-butter calls |
| Shop stock | Occasional, or common but bulky/costly | Central shelf space, cash on hand | A supplier trip during the day |
| Order per job | Rare, job-specific, expensive, or bulky | Lead time, a possible second visit | Frozen cash and dead stock |
The tiers form a ladder of closeness. Closer means faster to reach and more protection from a stockout, paid for with more slots and more cash tied up. The skill is putting each part on the lowest rung that still protects the job.
Put it on the truck when
- You use it on a large share of your normal calls.
- Running out means a stalled job and a return trip, not a quick swap.
- It is small and stable, cheap to carry and slow to expire.
- The supplier lead time is long enough that ordering per job would routinely cost you a second visit.
A part that is frequent, small, and painful to be without is truck stock, full stop.
Hold it at the shop when
Shop stock is the middle rung that most shops underuse. It fits parts you need often enough to want on hand, but not on every truck.
- The part is common but bulky or costly. Carrying it on every truck multiplies the space and cash by the size of your fleet. One shop shelf covers all trucks.
- A dispatcher can pre-stage it. When the call type is known at booking, the part rides out with the tech for that job without living on the truck permanently.
- Usage is real but moderate. Frequent enough that a supplier run mid-job would sting, rare enough that a fleet-wide slot is waste.
Shop stock is how you serve an occasional part once, centrally, instead of paying for it on every truck.
Order it per job when
- You use it rarely and cannot predict it from your call mix.
- It is expensive or bulky, so holding it freezes cash or space for little return.
- It is specific to one customer's exact equipment with no reuse.
- It goes obsolete or has a short shelf life, so holding it risks a write-off.
When you order per job, tell the customer the timeline honestly and book the return before you leave. See related: Emergency Parts Run vs Reschedule Decision Tree for the in-the-moment version of this call.
Let your history move parts between tiers
Placement is not permanent. The signal to promote a part toward the truck is your own special-order log: the same part ordered per job over and over is a shop-stock or truck item you have not recognized yet. The signal to demote is the freeloader audit: a truck part that has not moved in a season drops to the shop, and a shop part that never gets pulled drops to order-per-job. Work the common parts first. Getting the handful of items you touch every week onto the right rung is most of a tight parts operation.
Recap
- Frequent and job-critical goes on the truck.
- Common but bulky or costly, or dispatcher-stageable, goes on the shop shelf.
- Rare, job-specific, expensive, or perishable gets ordered per job.
- Watch the special-order log to promote, and the movement history to demote.
References
- See related: Special-Order vs Stock Decision Tree, The Part Not Available Decision Tree
- See related: Setting Reorder Points So You Never Run Out Mid-Job
- U.S. Small Business Administration (SBA), inventory and working-capital guidance
- Trade-standard practice for multi-tier parts stocking