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Home >> GMC >> 1999 >> C3500 HD 6.5 F, Automatic >> Repair and Diagnosis >> Engine Performance >> Application >> Engine/VIN Breakdown >> Engine/VIN Breakdown >> Engine Code Location
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Engine Code Location

NOTE: For description of engine (RPO) code, see 1999 MODEL COVERAGE  table.

  1. L01 & L34

    On lower left side of engine block, on engine-to-transmission mating flange.
  2. L29, L57 & L65

    On rear left side of engine block, on engine-to-transmission mating flange.
  3. L30, L31, LM7, LQ4 & LR4

    On rear left side of engine block, below left-side cylinder head.
  4. L35 & LF6

    On rear left side of engine block, on engine-to-transmission mating flange, OR  on rear right side of engine block, below intake manifold.
  5. LA1

    On left side of engine block, above starter.
  6. LN2

    On top front of rocker cover, OR  on rear left side of engine block, above starter.