Truck Stock + Parts Inventory Management
Why this matters
The right truck stock is the difference between first-time fix + a callback. First-time fix is the most impactful operational metric in service business - it drives customer satisfaction, productivity, AND profitability. A truck without the right parts means the tech leaves to get parts, customer waits, second visit charged, customer frustrated. Truck-stocking science is the answer.
First-time fix rate (the KPI behind this)
First-time fix rate (FTFR) = jobs completed on initial visit / total jobs visited.
Benchmarks by trade:
- HVAC service: 65 - 85% target (industry varies)
- Plumbing: 70 - 90%
- Electrical: 75 - 90%
- Appliance repair: 60 - 80%
- Pool service: 80 - 90%
- Pest control: 90 - 98%
Below benchmark: truck-stock issue OR diagnostic issue. Investigate.
Above benchmark: well-stocked, well-trained team.
What determines truck stock
Service patterns: most-common parts needed for typical service calls. For HVAC:
- Filters (multiple sizes)
- Capacitors (varied microfarads)
- Contactors
- Fuses
- Refrigerant (R-410A + R-32 stocked)
- Hardware (screws, fittings, gaskets)
- Cleaning supplies
Job mix: residential service truck differs from commercial truck differs from install truck.
Geographic + seasonal: cold-climate truck has different stock from desert.
Building the stock list
Step 1: Pull 12-month service history
CRM exports all parts used. Sort by frequency. Top 80% of parts used = potential stock candidates.
Step 2: Calculate value vs space
Each part: cost + size + usage frequency.
- High-frequency + low-cost + small: definitely stock
- Medium-frequency + medium-cost + medium-size: stock
- Low-frequency + high-cost OR large-size: stock at shop, not truck
- Specialty / rare: order on-demand
Step 3: Define the truck-stock list
Typical residential service truck: 40 - 120 line items.
Step 4: Set par levels
Each item: min on truck + reorder point.
Example: filters, par 10 of common sizes; replenish when below 4.
Truck organization
Layout matters:
- Permanent bins with labels
- Color-coding by category (electrical = blue, plumbing = green, etc.)
- Heavy items low for safety
- Frequently-used items at hand-height
- Mirror layout on multiple trucks for consistency
Shadow boards / labeled outlines: missing item visually obvious.
Inventory app (some CRMs): tech scans QR codes on parts; system tracks counts.
Restocking process
Daily:
- End of day, tech notes what was used
- Quick visual check; flag anything below par
Weekly:
- Tech submits restock list
- Service manager OR parts coordinator reviews
- Order placed
Monthly:
- Full inventory count
- Compare to system records
- Investigate variances (theft? Damaged? Missing record?)
Inventory theft / shrinkage
Realities:
- Parts on trucks invite shrinkage
- Tech might "borrow" for personal use
- Damaged items may be tossed without recording
- Lost items may not be reported
Loss prevention:
- Random truck inventory audits
- Parts tracked per job (CRM allocation)
- Variance reports flagged
- Trust-but-verify culture
Acceptable shrinkage: 1 - 3% of parts inventory annually. Higher = problem.
High-value parts management
Some parts are expensive:
- Refrigerant
- Compressor
- Control board
For these:
- Locked compartment in truck
- Tech accountable per piece
- High-value items stocked sparingly OR shop-only
Stocking by service line
Service truck (residential service + repair):
- Variety stock for diagnostics + repairs
- 40 - 120 line items typical
- Aim for 70 - 80% first-time fix on common services
Install truck (new equipment install):
- Materials specific to the install job + extras for variations
- Specific to scheduled job + buffer
- Restocked job-to-job
Maintenance truck (recurring service):
- Lighter stock (mostly filters + small parts)
- Predictable; can be lean
Specialty truck (sewer scope, hydrojet, leak detection):
- Equipment-specific + standard repair parts as backup
On-truck stock budget
A typical residential service truck carries:
This stock represents capital outlay; manage like an asset.
Replenishment supplier strategy
Primary supplier: handles 60 - 80% of orders
- Best pricing + reliable delivery
- Often offers payment terms (Net 30)
- Examples: Ferguson (plumbing), Source (HVAC), Hahn (electrical)
Secondary: backup + specialty
Third / fourth: rare specialty OR commodity
Build relationships with primary; quote shop for special projects.
Inventory management systems
Spreadsheet (small ops; 1 - 3 trucks):
- Manual tracking; OK but error-prone
- Time-intensive
CRM with inventory module (ServiceTitan, Manuall, Housecall Pro):
- Auto-allocates parts to jobs
- Tracks levels
- Reorder alerts
- Most contractors 5+ trucks
Standalone inventory app (Sortly, Stockify):
- Specialized for inventory
- Separate from job management
- Less common in service business
Most established service businesses use CRM-integrated inventory.
Standardization across trucks
For multi-truck operations:
- Same layout
- Same labeling
- Same par levels per item
- Tech moving truck-to-truck doesn't waste time finding parts
Standardization reduces:
- Lost parts
- Incorrect stocking decisions
- Tech confusion
Common stocking mistakes
Stocking what tech "thinks" might be useful
- Reality: 80% of jobs need 20% of possible parts
- Stock the 20%; rare parts on-demand
No par levels
- Tech "thinks they have enough"
- Customer waits while tech goes for parts
- Set par levels + enforce
Bulk-buying low-use items
- Item sits for years
- Eventually obsolete OR expired (refrigerant restrictions, etc.)
- Buy only what you'll use in 12 months
No truck audits
- Inventory drifts
- Stock gaps invisible
- Monthly audit catches problems
Tech-specific layouts
- Each tech sets up their own truck differently
- New techs lost on different trucks
- Standardize across fleet
ROI of well-stocked trucks
A truck with 70% first-time fix vs 50%:
- 8 jobs/day vs 6.5 jobs/day (assuming average 1.5 callback rate on poor stock)
Stock investment + management cost: ~ to maintain proper levels.
Net ROI on truck stock discipline: significant.
The single most-impactful truck-stocking decision is the SHADOW BOARD approach - outlined cutouts of where each part goes, labeled clearly. Missing items are visually obvious in 1 second. The tech can self-audit on every job. The dispatcher can spot-check from outside the truck. Most contractors organize by "tech preference" + can't tell at a glance what's missing. Shadow boards force discipline + dramatically improve restocking. Worth the 2 - 4 hours per truck of initial setup.
References
- ServiceTitan inventory module documentation
- HVAC + Plumbing supplier programs (Ferguson, Source, Hahn)
- Industry first-time-fix benchmarks (PHCC, ACCA)
- Manuall internal: Weekly Truck Inventory Audit, Dispatch Board Management + Optimization