Toyota Australia has fixed thousands of faulty or clogged diesel particulate filters across HiLux, Prado and Fortuner models made since 2015 – and now it claims the newly updated versions of those cars have a system redesigned in such a way as to avoid past problems.
While the company is at the centre of a legal dispute over vehicles sold between 2015 and 2019, Toyota insists it has fixed the problem and continues to urge customers to come forward if they are not happy.
However, expert evidence presented to the Federal Court claimed the original Toyota DPF system was "defective" in its design and prone to failures. Toyota tried to have the evidence dismissed, but it was accepted as part of the Federal Court's consideration to any possible fines or remedial action.
Given that it's still a hot topic and many customers remain unconvinced that the problems have been solved, CarAdvice obtained more details about the changes to the latest DPF hardware and software changes on models since 1st May 2020.
Previously, Toyota’s statements pointed towards software and hardware changes without any further details.
However, now armed with some additional information from Toyota, CarAdvice can outline significant changes to the design of the so-called ‘fifth injector’ and diesel oxidisation catalyst – a running change introduced in May 2020 – along with software changes of how the DPF operates.
The fifth injector, which is there to increase temperatures within the DPF when required for active regeneration, now has extended water jackets around the tip of the injector for better cooling ability.
Software changes, introduced at the same time, allow better operation of this new fifth injector design.
The diesel oxidisation catalyst (DOC), a honeycomb structure of various metals which converts exhaust gasses into being less harmful, has also been redesigned for more effective performance.
Anecdotally, during our time with new HiLux and Fortuner since these changes have been made, the DPF has been automatically going into an active regeneration mode more regularly – up to five times in one vehicle in less than one week, including on a freeway run.
This is accompanied by new updates through the multifunction display, indicating when either an automatic regeneration cycle has begun, or if a manual burn is required. There is also now DPF level indicator.
The changes have been undertaken because of widespread problems with Toyota's 2.8-litre and 2.4-litre DPF system, which precipitated legal action against the manufacturer.
Bannister Law, who is heading up a class action against Toyota, says over 250,000 vehicles sold between 1st October 2015 and 23rd April 2020 were affected, including popular HiLux, LandCruiser Prado and Fortuner models.
Recently deemed ‘defective’ by a court-appointed independent report, faulty DPFs will emit excessive white acrid smoke, has the potential to increase fuel consumption in some cases, and requires a visit to the dealer to remedy.
Along with having this new DPF design for their 2.8-litre and 2.4-litre diesel vehicles, Toyota has also extended a ten-year warranty on affected vehicles with faulty DPFs.