6.2L LS3 V8 · Crankshaft

Main bearing journal runout limit

Specification

GM does not publish a discrete limit for this measurement on the LS3. See the notes below for what bounds it and the accepted service practice.

Measured with Dial indicator.

Notes

GM SI document 2055077 "Engine Mechanical Specifications (6.2L LS3)" does not publish a single discrete "main bearing journal runout" limit. Related specs that bound this measurement: "Crankshaft Main Journal Out-of-Round – Service" 0.008 mm (0.0003 in) and "Crankshaft Main Journal Taper – Service" 0.02 mm (0.00078 in). The closest explicit "runout" value is "Crankshaft Rear Flange Runout" 0.05 mm (0.002 in), which uses the same dial-indicator measurement method on the crankshaft. Industry practice for LS engines uses 0.05 mm as the main journal runout service limit when measuring TIR with the crank supported at outer mains and reading at the center main — consistent with the rear flange spec.

Sources

  • GM Service Information: Engine Mechanical Specifications (6.2L LS3), Document ID 2055077Captured 2026-05-28

Values are cited as facts. We do not reproduce the manufacturer's prose, table layout, or diagrams.