Truck stock is the inventory of parts, materials and consumables kept on a service vehicle so the technician can complete common repairs without a trip to the shop or supply house.
Some companies call it van stock or rolling inventory. It is still company inventory, just stored on wheels.
How to measure truck stock
The most useful measure is fill rate: how often the truck had what the job needed.
Truck stock fill rate = Jobs completed with parts on the truck ÷ Jobs that needed parts
Say technicians needed parts on 200 jobs last month and had them on the truck for 170. Fill rate is 170 ÷ 200, or 85%. The other 30 jobs meant a supply run, a return visit or a delay.
The second measure is how much stock sits still:
Slow stock share = Value of items not used in 90 days ÷ Total truck stock value
High fill rate with a high slow stock share means you are carrying too much to get there.
Why it matters
Every missing part creates a trip. Either the technician drives to the supply house mid-day, which adds drive time and pushes every later job, or the job ends and a second truck roll gets booked. Both show up in your first-time fix rate.
That makes truck stock a scheduling issue as well as an inventory one. A supply run in the middle of a tightly booked day can make the afternoon unreachable. Stocking the parts that cause most return trips is usually cheaper than the drive.
Build the stock list from your own records. Pull the parts used across the last year of work orders, rank them by how often they were needed, and stock the top of the list. Add parts that are rarely used but would end a job if missing. The field service inventory management guide covers restocking and counts.
A common mistake
Letting each technician stock their own truck without a standard list. Trucks drift: one carries too much of what that technician likes, another runs out of basics. A standard list per truck type, with a regular restock, keeps fill rates even across the crew.
Related terms
- First-time fix rate improves when the right parts are on the truck.
- Truck roll counts the return visits that missing parts create.
- Job costing needs truck stock usage recorded per job.
Common questions
How much truck stock should a technician carry?
Enough to complete the jobs you most often send that truck to, without carrying parts that sit for months. Start from your parts usage data and adjust each quarter.
How often should truck stock be counted?
Many companies restock weekly from usage records and do a full count monthly or quarterly. Counting finds shrinkage and parts used but not recorded.
Should truck stock be charged to jobs?
Yes. Record every part used against the work order. Otherwise job costs look better than they are and the truck slowly empties without anyone knowing why.