Glossary › T

Low coupling

Trailers that are coupled lower than usual ca 750-850 mm. The coupling is usually positioned far under the truck near the rear axle that gives the alternative expression ‘under coupled’. Such coupling allows the distance between truck and trailer body to be as small as possible because the pivot point is moved. The available load deck length can be considerably longer than for conventionally coupled vehicles.

Tailored Blanks

Vehicle or bodywork components from laser welded sheet metal. After welding they are pressed to the correct shape and are very strong. Made from various material thickness and material quality.

Tandem axles

Trailers with two axles up to 20 tonne total load in Germany. When the distance between axles is one meter or less the axles are considered to be one axle and do not require driver to have german driving licence class C, CE (old class 2). Also popular these days are tridem-trailer (with 3 axles).

Tandem low bed trailer

Trailers with low deck height and tandem axles. Usually a class B-, BE-, C1-, C1E- (old class III-) trailer for small construction equipment.

Tank capacity

The internal volume of a tanker measured in cubic metres (m³).

Tank container

Tanks which are contained within a frame with dimensions and fittings in accordance with ISO standards.

Tank reinforcement

Recent safety regulations require tank semi-trailers to have the tank material strengthened along its length so that the tank is less likely to be damaged or torn in the case of an accident.

Tank trailer

Tank bodied trailer for liquid loads. Tanks are made from GRP, aluminium, V2A, V4A and mild steel.

Tare weight

Weight of a vehicle when empty.

Tare weight

Term used in Eastern Germany for weight of vehicle when empty.

Tare weight

The weight (or mass) of an unloaded trailer.


Product name from the first manufacturer of curtainsiders in England.


Trailer Central Electronic –the electronic central system of a trailer.


Abbreviation of the term Transfrigoroute Deutschland – an association for temperature controlled traffic.

Tele light 24

Product name for a remarkable three-axle semi-trailer that can be extended from 13.5m to 23m and is hydraulically steered. Manufactured by the Dutch company broshuis.


Term for the communication between trailer, truck and customer.


Drawbars, trailer chassis or semi-trailers that can be extended and retracted (up to 6000 mm) to change the load deck size.

Telescopic drawbar

Drawbars can be extended by 6 x 100mm to suit allowable overall vehicle length.


Manufacturer of retarder brakes for trailers.

Temperature recorder

Refrigerated vehicles use this to maintain a permanent transport temperature. Also used as a record of temperature for insurance claims.

Temperature sensitive goods

Goods which are transported by tank, silo or box body using cooling or heating equipment to maintain as constant a temperature as possible.

Temperature zone

Load chambers in refrigerated bodies that carry various goods at various temperatures.

Tension chains

Tippers which transport bulk goods e.g. sand, gravel, etc. may have tension chains spanning between side walls to help prevent the walls bellying out.


Leading manufacturer of brake shoe linings.


Leading European manufacturer of refrigeration equipment for vehicles.

Three-way tipper

Trailer or body that can be pneumatically or hydraulically tipped three ways – to both sides and to the rear.

Threshold strip

Door thresholds of refrigerated vehicles may be raised to contain any liquid accumulated on the vehicle floor.

Through loading system

This is a system that allows goods to be loaded and unloaded from the rear through the bulkhead of a trailer and the rear doors of the tractor unit across a platform between the two.


Abbreviation for Transfrigoroute International an association for temperature control traffic.

Tilt board pockets

Steel pockets fitted to the posts of a tilt body which carry the cargo control boards.

Tilt boards

Wooden or aluminium boards that are used for cargo control above the drop-sides of tilt bodies.

Tilt corner posts

The front and rear vertical posts of a tilt body which are usually removable or hinged. These are used for fixing drop-sides and to support tilt bodywork.

Tilt cover

Simple tilt covers that are fixed to drop-sides under tension.

Tilt cover fixing

Fixing equipment for tilts on lightweight vehicles.


Long tilt bodied swap body up to 45 foot long.


Leading European trailer rental company.

Tipper cover

Covers (may be hydraulic rigid covers) are used on tipping trailers to avoid dusty materials being blown out at speed.

TIR plate

Transport International Routier customs plate.

Titanium alloy

Internal lining material for tankers which transport corrosive liquids.

Top coat

Term used for the inner and outer surface of insulated trailers.

Top loading system

Tankers which can be loaded from above rather than from below.


Term used for a safe tank vehicle with futuristic safety characteristics.

Towing eye

Available in 40mm and 50mm diameters. The wearing part of a drawbar.

Towing hook

Found on the rear of trailers and semi-trailers.

Trac Lift TL 20

Prime mover for swap bodies from the manufacturer Mafi Transport Systems.


This refers to the alignment of an axle or group of axles that ensures the axle runs in a straight line and thus reduces wear on tyres.


General term used for guide rails in vehicles e.g. floor tracks for roll cages.


An anti-theft lock for the drawing eye of a trailer draw bar.


Generally used European term for trailers and semi-trailers

Trailer brake valve

The valve on a trailer to which the brake load controller is connected.

Trailer combinations

Several compatible wheel groups (load modules) combined to provide a desired length and load capacity (usually low loaders).

trailer tax®

German publication for estimating value of used trailers, bodies and semi-trailers. See and

Trailer tel

Electronic information and navigation system from Kögel.


Manoeuvre and drive assistance for car trailer couplings/car trailers.

Trailing curtain

Continuous unloading or walking floor systems may have internal walls that move with the floor. These walls have a trailing curtain at the bottom to ease discharge and help clean the vehicle.

Trailor axles

Former name of French axle manufacturer now known as SNB.

Tri-stop cylinder

Spring operated cylinder with three functions : foot brake, handbrake and pressure loss in the brake system.


Dutch manufacturer of chassis and steering axle equipment.

Tridem axles/aggregates

Three axled trailers based on tandem configuration i.e. 3 axles centrally positioned under the trailer. Occasionally used for 24 tonne maximum weight trailers. High tyre wear if no lift axle fitted.

Trilex rims

A one-piece or three-piece rim fitted with so called ‘wheel stars’. Trilex rims are lighter but more expensive than standard one-piece tubeless rims.

Triple bridge vehicle

Road train combination with a total weight of 17.5 t comprising a double axle tractor unit up to 7.5 t and a single axle trailer up to 10 t axle load. In Germany these vehicles could previously be driven with a third class HGV licence taking advantage of a loophole in the German regulations but this is no longer the case.

Trough securing section

Used to secure removable troughs in vehicle floors.

Truck-lite LED

Side marker lights from the American manufacturer Truck-lite using light emitting diodes rather than bulbs.


Leading manufacturer of vehicle and body heating equipment.


Liquid gas heating for load space.

Tubular frames

Often fitted on top of drop-sides for cargo control. Animal transporters also have tubular frames to protect the animals.

Tubular framework

The basic construction of many self-supporting closed bodies. Usually a hollow box section frame.

Tubular meat rail

Found longitudinally under the roof of refrigerated bodies with fittings for the rail systems in slaughterhouses. Hanging meat is transported on these rails.

Tubular retracting step

Usually fitted below rear doors to aid access. Can be stowed under the body when not in use.


Term used for machines used to move semi-trailers in docks and ferries.


Current name for the manufacturer of former Thyssen steel swap bodies.


Manufacturer of low weight wheel rims.

Tunnel construction

Term refers to trailer construction from the manufacturer Krone with a special neck giving a low deck height using standard 385/65 tyres. The longitudinal frame butts up to a semi-circle that carries the dynamic and static loads. The lack of front neck allows a lower chassis construction.

Turning angle warning signal

A light flashes or sound is made at the limit of a coupling’s turning angle.

Turning dimension

The maximum increase in brake drum diameter specified by the manufacturer to which the brake drum may be turned and increased for re-use.

Turning impulse

Applied by the load when transporting long materials. The turning radius is set via cylinders by the material resting on the fifth wheel.

Turning kinetics

General term for technical equipment used to turn trailers and semi-trailers.

Turning limit

The limit to which a component can be turned.

Turning point

This is the coupling point of a trailer on the tractor unit.

Turning radius

The distance from the king pin to the neck of a semi-trailer.

Turning steering frame

The front part of a trailer which carries the turntable and is connected to the main chassis frame.


Component which allows a front axle to turn and at the same time carry the axle load.


Turntables are used to turn multi axle trailers. Turntables are in two halves running on a ball bearing.

Turntable-rod steering

Steering of the rear trailer axle is achieved from the king-pin via rods.


German Association for Technical Inspection. Testing institution for trailers and semi-trailers that must be tested annually. Trailers with total weight below 2 tonne and caravans must be tested every two years.


Product name for a newly developed plastic with a very low K-value for manufacturing refrigerated bodies.

Twist locks

Locking device for securing container corner castings.

Twist locks (1)

Fitted to vehicles and used to secure containers and swap bodies by their corner castings.

Type approval

Testing system from German Railways for standard containers and vehicles that can be transported by rail.


Explanation of tyre references e.g. 175/70 R 13 T : 175mm tyre width; 70 = the tyre wall is 70% of the tyre width; R = radial tyres; 13 is the internal diameter in inches; T is the speed index T = tubeless.