Replacing every vehicle at a fixed age is simple, but it is not always economical. Mileage, reliability, warranty, resale value and the way the business uses the vehicle matter more than age alone.
Watch cost trends rather than birthdays
Maintenance cost, tyre spend, downtime and fuel use often tell you more than vehicle age.
High-mileage vehicles may need a shorter cycle
A van covering intensive daily routes can reach the expensive part of its life much sooner than a low-mileage pool car.
Residual value matters
Keeping a vehicle longer avoids another purchase, but it can also mean selling after a steeper fall in value or when buyers are less interested.
Technology can change the calculation
Safety equipment, emissions requirements and electric-vehicle capability can make replacement strategically useful even where the old vehicle still works.
Renew vehicles and insurance deliberately
Replacing several vehicles can change fleet value, repair costs and driver allocation. It is a sensible point to review cover rather than assuming the existing policy remains the best fit.
Example: why keeping a van longer is not always cheaper
| Year 3 | Year 6 | |
|---|---|---|
| Estimated annual depreciation | £4,000 | £2,000 |
| Maintenance and tyres | £900 | £2,200 |
| Downtime / replacement hire | £250 | £1,000 |
Older vehicles may depreciate more slowly but cost more to maintain and keep on the road. The sensible replacement point is often where the combined cost curve starts moving the wrong way, not simply when finance ends.