MAHLE Original® timing belts are specifically engineered for each vehicle application. Belts should be replaced when they become frayed, stretched or worn. MAHLE Original roller chains are used on many applications including high performance, OHC engines and heavy-duty truck engines. Roller chains generally have reduced wear characteristics and increased endurance limits. Chains should be replaced when they become worn or stretched, as this will affect the timing of the engine and result in poor performance. A full line of dampers, idlers, tensioners, and guides are provided by MAHLE Clevite for import and domestic engines. Timing chain tensioners reduce noise and prolong the chain life. Tensioners also compensate for slack in a worn or stretched chain or belt, and help to maintain the correct valve timing. All MAHLE Original idlers, tensioners, dampers and guides are precision-made to match and enhance the life of the timing system. Because these parts play an important part in keeping the engine running smoothly, they should always be replaced when the belt or chain is installed.