Toyota T100 timing chain or belt issue causing decelerating slapping sound and non-turning belts on Toyota T100

Some Toyota T100 owners report experiencing a decelerating slapping sound that may indicate issues with the timing chain rather than a timing belt. This metallic slapping noise could suggest a loose timing chain making contact with the timing chain cover, which may occur intermittently or constantly before a complete chain failure. Additionally, some owners find that a mis-adjusted tensioner can lead to noise as the chain rubs against engine components. It is crucial for owners to check the timing chain tension, adjust it if necessary, and ensure that the guides and tensioners are functioning properly. Proper lubrication of the guides, tensioners, and chain with high-quality lubricant is also essential to prevent excessive wear and noise. In cases where timing chain guides are broken, the chain may slap during deceleration. Therefore, if a slapping sound is heard, it is advisable to have the timing chain inspected and potentially replaced to effectively address these concerns.