Overview
Everyone talks about preventive maintenance like it is a discipline problem. Schedules, checklists, intervals, due, overdue. Just follow the program and the equipment stays up.
But here is what we keep running into: the shops that are struggling with PM outcomes are not the ones skipping services.
After sitting down with hundreds of fleets and walking through their actual PM workflows, we have found that medium and large fleets almost never skip PMs. The oil gets changed, the brakes get inspected, the filters get swapped, the boxes get checked. PM C, B, A, dutifully done, almost always right on schedule.
Yet equipment still goes down in ways that feel like they should have been caught. Warranty claims still get missed, compliance gaps still show up in audits, and recurring issues still do not get flagged until they become failures.
The problem is not that shops are not doing PMs. The problem is that the way PMs are structured today, with paper checklists, handoffs, and re-entry, systematically filters out the most valuable information before it ever reaches the system. Critical observations never become data. As a result, fleets cannot trend it, act on it, or prove it happened when someone comes asking six months later.
What the workflow actually looks like
Here is what happens at a typical heavy-duty shop when equipment comes in for service.
A driver, maybe operating a tandem axle dump truck, maybe hauling in a salt spreader or a reefer, fills out a service request. In many shops, that is still a triplicate paper form pulled from a carbon-copy book stored with the asset, often one of about 100 forms dedicated to a single piece of equipment.
The driver writes the basics: equipment number, meter reading, "Annual PM." Maybe there is a short note if something feels off. Then they walk the form and the keys into the shop, find the supervisor, explain the issue verbally, and leave.
The supervisor takes that paper and manually creates a repair order in whatever system the shop runs, whether that is an ERP, a fleet management platform, or a homegrown database. That repair order gets printed and handed to a technician. If it is a PM order, it includes a checklist, often paper. If it is a standard repair, it is a different format.
Either way, technicians fill out time cards throughout the day, logging repair-order numbers, hours worked, and whether the job is partial or complete, then turn everything in at the end of the shift. The supervisor often re-enters all of it back into the system.
Screen or paper to person to screen to paper to screen again. That is the loop.
The margin-notes problem
The data-entry burden is painful, but it is far from the biggest cost.
When an operator fills out the service-request form, the formal complaint usually makes it into the system. The meter reading usually makes it in. Selected operations make it in. What often does not make it in are the margin notes, whether they are scrawled on the form itself or added in informal internal comments.
Things like:
- "Hydraulic line starting to sweat."
- "Wiring harness rubbing frame."
- "Spreader chain tension seems loose."
- "Might need front pads next service."
These are not failures. They are observations and early signals, the kind of information that becomes incredibly valuable if it gets captured and completely invisible if it does not.
Right now, it gets written in the margin, circled, underlined, sometimes scribbled diagonally across the bottom of the page. A technician might explain it verbally to the supervisor during the handoff, but that conversation disappears the moment they walk out the door.
What makes it into the system is the formal complaint. What does not make it in is the technician's nuance, the "not yet, but watch this" observation that is, in many ways, the entire point of preventive maintenance.
PM is not just about documenting what failed. It is about surfacing what is starting to trend. You cannot trend what you never captured.
Checklists that do not match the equipment
PM orders are supposed to include a checklist tied to the specific asset. Monthly, quarterly, annual, each interval with items to inspect, service, or replace. In theory, these checklists ensure every piece of equipment gets the right maintenance at the right time.
In practice, these checklists often remain static.
One fleet described their checklists as "woefully out of date." Not because they do not care. They actually have an active internal project trying to fix the problem. But the process of updating checklists is so manual that keeping them current becomes its own workstream.
Equipment gets retrofitted, components get swapped, attachments change, manufacturer recommendations evolve, and the checklist stays frozen in whatever state it was last printed.
So a technician completes a PM on a 10-cubic-yard Swenson spreader, checks the boxes on a checklist that may not reflect what that spreader actually needs today, and maybe writes a note in the margin: "Hydraulic line starting to seep, monitor." That note lives on paper and never gets structured into the asset history.
Two months later, the line fails. The truck is down during a snow event. There is an emergency repair, and someone asks, "Did we not just do the PM?"
Yes, the PM was done. The technician even caught the issue. But the observation never became data.
The stack
This is the part nobody talks about.
Paper accumulates. PM sheets get clipped together. Vendor invoices get stapled on top. Margin notes stay buried in the pile. Maybe they get scanned eventually, but often they do not.
Then six months later, a compliance review happens, or a warranty audit, or a legal discovery request. Someone pulls the file and starts piecing things together, only to find that the PM checklist was not fully completed, a time card does not match the system hours, a vendor invoice was never entered, and a note about monitoring a hydraulic line never became an action item.
Now the fleet or service provider is reconstructing history from a pile of paper. Not because anyone was careless, but because the entire system relies on perfect manual continuity across every handoff, every shift, every day.
Why this actually matters
The biggest cost of all of this is not the supervisor hours burned on double data entry, though that cost is real. It is the loss of structured memory.
When observations do not become structured data, you lose the ability to detect trends. When margin comments do not become follow-up tasks, recurring issues do not get flagged until they become breakdowns.
No single moment feels catastrophic. It is destruction by administrative friction, slow and steady, until something forces you to look backward.
Preventive maintenance works well when small signals are captured early. Today's PM workflows are decent at recording events and checking the box, but they are terrible at capturing weak signals and turning them into action.
Every fleet we talk to can diagram exactly where the process breaks down. They know where data gets lost and where notes disappear. They are not waiting for someone to tell them the workflow is inefficient.
The difference between preventive and reactive maintenance usually lives in the margin. Right now, that margin is a piece of paper in a stack on a supervisor's desk.
In this three-part series, we explore how to capture the power of the margin without losing the simplicity of a paper PM.
Axle is building the system of execution for fleet repair and maintenance, so techs, fleet managers, and fleet executives can focus on trucks, not mindless admin.