Interior lining

Interior trim determines the comfort, acoustic experience and professional condition of the cab. This category includes headliners, door panels, A-, B- and C-pillar trims, dashboard trims, side wall panels, floor coverings, insulation mats, sleeper cab panels and cover caps. For MAN TGL, TGM, TGS, TGX and TG3, Mercedes Atego, Axor, Actros, Arocs, Antos and Econic, as well as TGE, Sprinter, Vito, Citaro, Tourismo and Neoplan buses, the shape, mounting, colour scheme and cut-outs vary considerably by version. Therefore, always identify interior trim parts using the vehicle chassis number. A visual comparison or selection based solely on the model name is never sufficient.

Cab trim is generally made from moulded thermoplastics, ABS plastic (acrylonitrile butadiene styrene), polypropylene, fibreboard, textile, foam layers and acoustically absorbent materials. The choice depends on the location: door panels must be impact-resistant and moisture-resistant, headliners must retain their shape during temperature fluctuations, and floor coverings must be wear-resistant, non-slip and easy to clean. Sound-insulating panels often combine a heavy mass membrane with an open-cell absorption material to reduce rolling noise, airborne noise and vibrations from the chassis and cab suspension.

When identifying parts, pay attention to the cab variant, roof height, sleeper cab, door version, left- or right-hand position, colour code, storage compartments, speaker openings, controls and cut-outs for wiring harnesses. For example, a door panel for a MAN TGX XXL is not interchangeable with one from a TGX XL or XLX; the same applies to trim parts in Mercedes Actros cabs such as ClassicSpace, StreamSpace, BigSpace and GigaSpace. In buses, interior panels also depend on the seating layout, emergency exits, HVAC (Heating, Ventilation and Air Conditioning) ducts and passenger amenities.

Typical faults include loose clips, torn mounting tabs, discoloured surfaces, cracked artificial leather, sagging headliners, moisture stains, creaking panels and worn floor coverings. Especially in high-mileage vehicles, cab movement, defective silent blocks or worn cab shock absorbers cause increased vibrations. This creates play between the panel and bodywork, causes plastic clips to break and wears contact surfaces. A rattle in the cab is therefore not always solely an interior trim issue.

First systematically check for moisture ingress through the windscreen, roof hatch, door seals, condensate drain or cable pass-throughs. If in doubt, use a moisture meter to measure the insulation layer and inspect metal mounting points for corrosion. Locate creaking and rattling noises during a test drive on a rough road; then press individually on suspected panels while the cab is idling. Check clips, guide pins, screw bosses and mounting tabs for deformation. Also check whether wiring harnesses, speaker cables or HVAC air ducts behind the trim are loose or rubbing against a panel.

Remove interior panels using suitable plastic trim removal tools to avoid indentations, white stress cracks and damage to painted parts. Preferably replace trim with broken load-bearing tabs or torn mounting points completely; adhesive repairs often do not withstand continuous vibration loads sufficiently. Also renew deformed clips, sealing strips and insulation mats. Reuse only fasteners whose spring tension, diameter and retention are still within tolerance.

Clean contact surfaces, remove old tape or adhesive residue and, before final installation, check the free movement of window regulators, door locks, seat adjustments and seat belt mechanisms. Use only materials suitable for vehicle interiors, with adequate temperature resistance and low emission values. A correctly fitting part reduces resonance, prevents secondary damage to switches and wiring harnesses, and keeps the cab presentable. Thanks to technical support and a large stock of cab parts, Braem can help keep downtime during accident repairs to a minimum.