Automotive reconditioning firm DPF Clean Team says many dealerships do not cover DPF maintenance under standard vehicle warranties, and therefore replacement costs can be up to 20 times more expensive than cleaning the filter.
"DPFs are gaining importance in the public sector as Euro 6 engines become more common through routine fleet replacement, and via retrofits, to satisfy London's emissions zone," says Cameron Bryce, managing director of DPF Clean Team.
"But what many operators do not understand is that DPFs are not warranty-covered and therefore a blocked DPF is not the responsibility of a dealer or vehicle supplier," he continues.
"This is not just an issue for public sector fleets travelling through London, but to the entire country if ULEZs are to be rolled out on a national scale."
If ULEZs were to be implemented nationwide, Bryce recommends that each local authority should enforce routine testing of DPF efficiency. This would alert public sector fleet operators to a potential issue with a DPF before it becomes serious enough to breach emissions targets.