A new part for the previous generation Hilux
Toyota has not forgotten about the previous generation of its popular Hilux pickup, even with the release of a new model. The company’s division known as Toyota Upgrade Factory, which specializes in modifications and retrofitting, has introduced a new part designed to improve the handling of the old Hilux.
An unexpected solution for stability
One might expect new springs or a body reinforcement to improve handling. Instead, engineers created an aluminum underbody guard with aerodynamic fins. The part, named “Shibetsu Fin Undercover,” not only protects the underbody but also promises to increase stability and reduce sensitivity to crosswinds.
Engineering from Hokkaido
The development of this solution was carried out at the Toyota Shibetsu proving ground in Hokkaido. By studying airflows under the pickup’s body, engineers discovered that the large ground clearance causes minor vibrations. These vibrations, in turn, lead to uneven air pressure on different sides of the vehicle.
According to Toyota, the Shibetsu Fin Undercover “smoothes turbulent airflow around the vehicle, reducing the pressure difference between the left and right rear sections, and also improves stability during cornering, straight-line driving, and under external disturbances such as crosswinds.”
Technical details and production
Toyota claims that the small fins on the aluminum plate reduce vibrations with a frequency below 1 Hz to one-tenth of the original level. The accessory does not affect the pickup’s approach angle and retains access for oil changes.
Bringing this idea to life proved challenging. Stamping 5 mm (0.2 inches) high aerodynamic fins from a solid 3 mm (0.12 inches) thick aluminum sheet was an engineering challenge that several industrial companies initially declined. For implementation, Toyota joined forces with metalworking craftsmen from the renowned Tsubame-Sanjo region in Niigata Prefecture, combining high-precision multi-stage pressing with manual finishing on flexible machines.
Compatibility and price
The underbody protection plate fits Hilux models produced from August 2017 to August 2022, as well as models produced from July 2023 to October 2024. Its price is ¥75,900 ($470), including taxes and installation at an authorized dealer.
Previous experience with Shibetsu Fins
Interestingly, the Hilux is not the first Toyota vehicle to receive “Shibetsu fins.” Similar additional underbody components are offered for the Land Cruiser 250 Series. They are compatible with models produced from March 2024 and cost ¥31,680 ($200) including installation.
This move by Toyota demonstrates that the company continues to support previous generations of its vehicles by offering unconventional engineering solutions to improve their performance. Instead of typical suspension upgrades often offered by tuning shops, Toyota focused on underbody aerodynamics, a less obvious but potentially effective way to combat instability at high speeds. The collaboration with craftsmen from Tsubame-Sanjo also underscores the company’s commitment to preserving traditions of handcraftsmanship even in modern manufacturing, adding uniqueness to the product. Given that similar solutions are already being applied to the Land Cruiser, it can be assumed that Toyota sees potential in expanding its line of aerodynamic accessories for its SUVs and pickups.