flange of the axle tube. This approach allows existing vehicles to be converted to use portal gear lifts without modifying the axles (Volvo C303 or Unimog 404). Examples Vehicles fitted with portal axles include: AM General HMMWV and Hummer H1 International FTTS Land Rover Defender 130CC-R(hino) Mercedes-Benz G500 4×4² and G63 AMG 6x6 6x6 truck. Mercedes-Benz Unimog Porsche 597 Porsche 911 in Porsche 997 GT3 R Hybrid (2010) Praga V3S (1952-1989) - 3 ton all-terrain truck (6x6) Steyr Puch Haflinger Steyr-Daimler-Puch Pinzgauer Tatra T 805 small truck Tatra T 810 medium truck Toyota Mega Cruiser (Civilian model and JGSDF's High Mobility Vehicle) Volkswagen Type 2 (first generation) Transporter | Kombi | Microbus Volkswagen Type 82 Kübelwagen Volkswagen Type 166 Schwimmwagen Volkswagen Type 181 Volvo C303 Volvo C202 LuAZ/ZAZ 969 UAZ-469(Only military versions) In-line gearboxes A related development is the use of an epicyclic hub gearbox. This is mounted in-line with the halfshaft, so that there is no change in ride height. They are often used for large and heavy vehicles, where the wheel diameter already gives adequate ground clearance. The reduction gearbox allows the halfshafts to turn faster than the wheels, thus requiring less torque for the same power. This permits a smaller and lighter halfshaft and internal drivetrain. Hub gearboxes were an iconic feature of the Alvis FV600 chassis vehicles, such as the Stalwart and Saracen. The FV600 used a version of the DAF H-drive, with a single differential between sides and all wheels on each side linked by an internal driveshaft and bevel gearboxes to the halfshafts. This has no differential axle between wheel stations on each side and so 'wind-up' was a regular problem for these vehicles when driven on roads. If individual wheels were out of phase with their neighbours, possibly caused by cornering or slightly varying tyre diameter, this could place a considerable force on the gearbox, leading to breakages. For this reason, it was regular practice when driving on tarmac to bump the vehicle over a kerb or other object at times, to allow this wind-up to be released. On slippery surfaces like sand or mud there is enough slippage between the tyres and ground to dissipate the tension. They are now found on many large quarrying dump trucks and heavy plant. Manufacturing Today, portal gear lifts are manufactured for use in utility task vehicles (UTV). See also Dropped axle References Automotive transmission technologies