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12556307 - ZZ4 Crankshaft (Forged Steel)

This product may require vehicle validation(s) for proper fitment. Please contact us to confirm correct vehicle fitment and usage.

Availability: Replaced by 12670965


This forged steel crankshaft is used on all 2nd design ZZ4 350 engines after November 1998 and can be used to replace all cast or steel forged crankshafts on ZZ4 engines only. This crankshaft is made of 1053 steel and balanced to connecting rod P/N 10108688 and piston P/N 10159436. This crankshaft cannot be used on earlier ZZ design engines because the pistons change engine balance.

Application List



  • 12556307
  • 12556307
  • GM (General Motors)
  • Replaced by 12670965
  • New


Shipping Information

  • Item Requires Shipping
  • 55.0 lbs.
  • W9.0000” x H8.5000” x L27.6000”

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