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OEM crankshaft keyway
Replacement crankshaft keyway
Crankshaft Replacement Caution for GM 2.8L, 3.6L Engines
The keyway may be different from the original when installing an engine or replacing a crankshaft in vehicles with remanufactured engines.
Affects 2007-2010 models with 2.8L or 3.6L High Feature V6 engines (VINs D, T, V, 7 RPOs LP1, LLT, LY7).
If the original crankshaft has a keyway slot and the replacement crank has a hole then round pin P/N 12585420 must be used, then install the harmonic balancer. Install a new bolt and torque it properly. The harmonic balancer will not need to be changed. Be sure to follow all instructions included with the engine pertaining to oil pan, front cover, flexplate etc.
Some or all of this information was provided by the Automotive
Parts Remanufacturers Association (APRA). For more information on
technical bulletins available through APRA call 703-968-2772 or visit www.AutoBulletins.com.