Service intervals for a fleet that does different work

A single service interval across a mixed fleet is wrong for most of the fleet. The van doing 400 motorway miles a day and the van doing 60 miles across 40 stops have completely different wear, and the odometer will not tell you that.

Three clocks, and you need all three

• •Miles: right for anything where distance drives wear, mostly long-distance running
• •Engine hours: right for stop-start urban work, idling, and anything with a power take-off
• •Months: right for everything that degrades with time, including fluids, brake systems and rubber

The rule is whichever comes first. A vehicle that has done 3,000 miles and 600 engine hours has worked hard, and only one of those numbers says so.

Group by duty, not by vehicle type

Two identical vans doing different jobs belong in different service groups. Sort the fleet by what it does rather than what it is.

• •Long distance: high miles, low hours per mile, steady load
• •Urban multi-drop: low miles, high hours, heavy brake and clutch use, constant door cycles
• •Specialist and off-road: power take-off hours, dust, vibration, low speeds
• •Standby and occasional: low everything, and time-based intervals dominate

Idling is the invisible one

A vehicle idling with a chiller or a lift running is accumulating engine wear with the odometer stationary. Fleets that schedule on miles alone will systematically under-service exactly the vehicles working hardest, and the failures will look random.

Use your own failure data after a year

Manufacturer intervals are a starting point written for a general case. After a year of your own records, look at where failures cluster relative to the last service. Clusters just before the interval mean it is too long; failures spread evenly mean the schedule is not preventing that failure mode at all.

Do not let seasonal work drift

Gritters, refuse vehicles and agricultural fleets do most of their work in a short window. Service them out of season, before the window, not on a rolling interval that lands in the middle of the busiest month.