Timing gears can cause knocking sound on GMC S15

Problem overview

Timing gears may wear causing a mild to severe knocking noise from the front of the engine. Replacement of the timing gears is necessary.

1 person reported this problem

GMC S15 vehicles with this problem

1 model year affected

1990 GMC S15

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Submitted by Vehicle Owner · May 29, 2025

Published by RepairPal

Timing gears can cause knocking sound on GMC S15

Problem overview

GMC S15 vehicles with this problem

Need a diagnosis? Trust our GMC experts.

Search for another problem

Ask our experts about your GMC.