The TRIDEC steering system type TD-X is a mechanical steering system used primarily in distribution transport. A TD-X system enables you to steer the first and last axles of a 3 or 4-axle trailer, with the first axle countersteering.

The use of a TD-X steering system in combination with a special axle arrangement and an axle load reduction on the rear axle provides a solution to the problem of axle overload of the driven tractor axle in the case of partial loading.

The system consists of a fifth wheel plate (which replaces the usual fifth wheel), axle mounting frames and a transfer lever, which are connected by the steering rods. The TD-X fifth wheel plate has a king pin and a steering wedge that are automatically locked in the fifth wheel on the prime mover when the trailer is hitched. When the prime mover is turned, the turntable plate in the fifth wheel plate turns with it via the steering wedge thanks to the fixed connection. The steering rod transmits the steering motion to a steering lever located above the middle of the axle assembly via the bearing journal at the top of the turntable plate. This steering lever transmits the steering motion to the axle mounting frames on the first and last axles via steering rods.

The front steering rod consists of three parts, a front and rear piece and a tube member centre piece. The rear steering rods consist of one piece with steering ball joints. As a result of this solid connection, the steering motion is transmitted very directly and there is no play on the system. This connection also ensures that the axle cannot be steered in any way other than by the motion of the prime mover. This means that rutting and other external factors do not adversely affect the vehicle's stability.

TRIDEC steering systems steer with the vehicle moving both forward and in reverse. So the vehicle remains optimally manoeuvrable at all times.

The TRIDEC TD-X system is a low-maintenance system. Maintenance is limited to lubricating the turntables a few times a year and testing just a few bolt connections. This is possible because high-quality materials and a durable construction are used. The steering rod bearings patented by TRIDEC, for instance, are entirely maintenance-free, thereby lengthening the trailer's service life. The turntables are sealed using a special seal and are mounted with special shear-resistant bolts, making it no longer necessary to check these bolts. In addition, all lubricating points are centralised at a single, easily accessible point.

Thanks to a unique patented design of the fifth wheel plate and the axle mounting frame, the entire system can easily be removed from below. This saves you a great deal of time during service and renders a floor hatch in the bodywork unnecessary, which is particularly important for refrigerated vehicles.

TRIDEC has an advanced engineering department which is responsible for the entire technical preparation and processing of your order. By means of specially developed software, a turning circle calculation can be made that simulates the road behaviour of your trailer when cornering. Interference checks and construction recommendations provide you with a customised system for your chassis. This gives you a system with the perfect combination between optimum steering and reduction of friction.


Gümaş Otomotiv Sanayi ve Ticaret A.Ş.
Taksim Cad. No:33/A 34437,
Taksim - İstanbul

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