Parts inventory software for fleet shops: what to look for
Updated · Reviewed by Israel Margulies, founder and CEO of High Point GPS
Parts inventory software for a fleet shop tracks what is on the shelf, what is on order and what each machine has used, and it ties every part issued to a work order. Auto parts inventory software built for stores that sell parts usually lacks that link to the machine and the job. If a system can’t show you what a given truck cost in parts last year, it’s the wrong kind for a shop.
Reorder point
(Average daily usage × Lead time in days) + Safety stock
A hypothetical shop uses 2 hydraulic filters a day, the supplier takes 5 days and you keep 4 as a buffer: (2 × 5) + 4 = 14. Reorder when on hand plus on order drops to 14.
Two kinds of parts inventory software
Search for auto parts inventory management software or car parts inventory software and most results are built for parts stores, salvage yards and repair shops that sell to the public. They focus on catalog lookup, fitment by vehicle, pricing tiers, point of sale and customer invoices.
A fleet shop consumes parts on machines it owns or runs. It needs to know which unit each part went into, what it cost and when it will need the next one. That kind of system usually sits inside a maintenance platform (a CMMS) so the work order, the machine record and the stock all share one database. Some shops need both, for example a rental company that also sells parts over the counter, but most fleet shops only need the second.
The features that matter for a fleet shop
Check how each feature works on a phone. Technicians receive deliveries, issue parts and count bins away from a desk, and a system that only works on a desktop gets skipped.
- One record per part: part number, description, alternate or cross-reference numbers, preferred vendor, shelf location and unit cost
- Quantity on hand, quantity on order and a reorder point per part
- Issue to a work order, so the part comes off stock and its cost lands on the machine
- A spare parts list per machine, so the person picking parts sees what that unit takes
- Purchase orders that can be received in part, with stock and cost updated on receipt
- Cycle counts with variance in units and dollars
- Low-stock alerts and reorder suggestions grouped by vendor
- Reports on parts cost by machine, category and month, with a CSV export
Reorder points and the on-order trap
The standard textbook reorder point is average daily usage times the supplier’s lead time in days, plus a safety stock for late deliveries or a busy week. In the hypothetical in the formula box, 2 hydraulic filters a day, a 5-day lead time and a buffer of 4 give a reorder point of 14. The detail that trips up spreadsheets is what you compare that 14 against. Inventory engineering courses, such as the University of Iowa notes listed below, define inventory position as stock on hand plus stock on order minus backorders, and the reorder decision uses that position.
If your system compares the reorder point with stock on hand only, it will suggest a second order while the first is still in transit, and you’ll end up with double the filters you meant to buy. Ask any vendor whether reorder suggestions subtract units already on order. Then set reorder points for the parts that stop machines (filters for scheduled PM, common hoses, wear parts) first, and leave rare parts to order on demand.
Costing parts: average cost and physical counts
Parts prices change between orders, so the software has to pick a cost when a part is issued. Weighted-average cost is common in shop systems because it smooths those swings. As a hypothetical: 5 belts on the shelf at $36 and 10 received at $40 give (5 × 36 + 10 × 40) ÷ 15 = $38.67 per belt for the next issue.
Whatever method you use, the book quantity drifts from what’s on the shelf. Parts get used without being issued, returned without being logged, or put in the wrong bin. For businesses that keep a perpetual (book) inventory for tax purposes, IRS Publication 538 says you must take a physical inventory at reasonable intervals and adjust the book figure to match. A shop that counts a few bins every week finds those errors while they’re small, instead of once a year.
Linking parts to machines and service records
Parts history is part of a machine’s maintenance record. For motor carriers, 49 CFR 396.3 requires records of inspection, repairs and maintenance for each vehicle, showing their date and nature, kept for one year and for six months after the vehicle leaves the carrier’s control. A work order that lists the parts installed is the easiest way to meet that and to back up a warranty claim later.
A spare parts list per machine also lets you plan purchasing. Open next month’s PM work orders, add up the filters and belts those machines list, and order the shortfall before the jobs start. When parts cost by machine climbs year over year, you have a figure to bring to the replace-or-keep discussion instead of a feeling.
Free parts inventory software and spreadsheets
A spreadsheet works for a one-person shop with a short parts list and one parts room. It breaks down when two people edit it at once, when nobody updates it after issuing a part, and when you need on-order quantities or parts cost per machine. Free parts inventory software can be a step up, but read the limits before you load your data: user caps, item caps, no purchase orders, or no link to work orders.
Whatever you choose, make sure you can export everything to CSV. Your parts list, vendor list and history are yours, and you’ll want them if you ever move systems.
Questions to ask in a demo
Bring a real example from your shop, such as last month’s filter order or a part that ran out, and ask the vendor to walk through it live.
- Show me a part being issued to a work order from a phone. Where does its cost go?
- Do reorder suggestions account for parts already on order?
- How does receiving work when only half the order arrives?
- How do you handle a part with two supplier numbers?
- Can a technician receive a delivery without being able to create purchase orders?
- What does a cycle count look like, and how are variances posted?
- Can I see parts cost per machine for the last 12 months?
Parts inventory in FleetZap
FleetZap’s parts module is part of the maintenance platform, so parts and work orders share one record per machine. Each part has quantity on hand, a reorder point, a shelf location and a weighted-average cost, with units on order shown next to stock. Each asset lists the spare parts it uses, with quantity per job and live stock, and the work order part picker shows that machine’s spares first. Parts used on a work order come off stock at the moment they’re used and are costed to the machine.
Purchase orders go from draft to ordered to received, in part or in full, or close short; receiving updates stock and average cost, and big orders can wait for an admin’s approval. Reorder suggestions top parts up and are grouped by vendor. Stock counts run on a phone or a printed sheet for every part, the low ones or one location, and post the variance in units and dollars. Technicians can receive deliveries but not buy, and low-stock alerts arrive in the app and by email.
Key takeaways
- Give a part a reorder point once it has held up a job; until then, order it on demand and keep the shelf for parts that stop machines.
- At go-live, count and load the parts you issue most each month first, and add slow movers the first time someone touches them.
- Limit who can adjust stock outside a work order, receipt or count, because every unexplained adjustment is a variance nobody can trace.
- Recheck safety stock whenever a supplier’s lead time changes, rather than on a fixed date.
Sources
FleetZap Maintenance
Work orders, PM, parts, compliance, assets and KPIs. Explore FleetZap Maintenance.
Frequently asked questions
Is there free parts inventory software?
Yes, several tools have free tiers or open-source versions, and a spreadsheet costs nothing. Check the limits before you rely on one: caps on users or items, no purchase orders, no partial receiving, and no link to work orders or machines. For a fleet shop the missing work order link matters most, because without it you can’t see parts cost per machine.
What is a spare part management system?
A spare part management system tracks the parts kept on hand to repair and service equipment: what is stocked, where it sits, how many are on order and which machines use each part. Good systems set reorder points, record every part issued to a work order and support regular counts, so the shelf matches the books and machines aren’t left waiting.
How do I track auto parts inventory for a fleet?
Give every part one record with its number, vendor, shelf location and cost, then issue parts only through work orders so each vehicle carries its own parts history. Set reorder points from usage and supplier lead time, receive deliveries against purchase orders, and count a few locations every week. Software that ties parts to vehicles and work orders makes this far easier than a spreadsheet.
How often should a shop count its parts inventory?
Many shops cycle count instead of doing one big annual count: a few bins or part groups every week, with expensive and fast-moving parts counted more often. IRS Publication 538 requires businesses keeping a perpetual inventory to take a physical inventory at reasonable intervals and adjust the books, and frequent small counts make that adjustment small.
What is the difference between parts inventory and MRO inventory?
Parts inventory usually means stocked repair and service parts for specific machines, such as filters, belts, hoses and wear parts. MRO inventory, for maintenance, repair and operations, is broader and also covers shop consumables, tools, fasteners, lubricants and safety supplies. Many shops track stocked parts item by item and expense low-cost consumables in bulk.