A whining or buzzing type noise may develop from the timing chain area caused by excess slack in the secondary timing chains. Nissan has issued a service bulletin (NTB09-128) regarding this issue. Replacement of both secondary timing chains and their tensioner shoes will be necessary to repair this concern. As part of this repair, the engine oil and filter should also be replaced.
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Some of the bolts that attach the engine oil cooler and filter to the engine may have been manufactured below specification strength. As a result, the bolt may break at the oil filter attachment point, which can cause an engine oil leak. Loss of too much engine oil can result in loss of oil pressure and the engine could seize, increasing the risk of a crash. Dealers will replace the connector bolts to correct this concern.