Product Description
Michigan Motorsports LS Harmonic Balancer Crankshaft Damper Bolt
Direct Replacement for GM #12557840 – Made in the USA
The Michigan Motorsports LS Harmonic Balancer Crankshaft Damper Bolt is a high-quality, USA-made replacement designed to meet or exceed OEM specifications. GM requires the balancer bolt to be replaced each time the engine is disassembled and the harmonic balancer is reinstalled. This bolt is a direct replacement for GM #12557840 and is compatible with most GM Gen 3, 4, and 5 LS/LT series engines.
Key Features
- OEM specification: Direct replacement for GM #12557840.
- Made in the USA: Precision-manufactured for strength and durability.
- Required by GM: Must be replaced whenever the harmonic balancer is reinstalled after engine disassembly.
- Wide compatibility: Fits most GM Gen 3, 4, and 5 LS/LT series engines.
Fitment
- GM Gen 3, Gen 4, and Gen 5 LS/LT engines
- Will not fit: LS7, LS9, LT4, LT5, and Grand Sport LS3 Corvette
