Revised Cylinder Head Bolt Torque Specification and Tightening Sequence for 1994-2002 GM 3.1L and 3.4L Engines - Engine Builder Magazine

Revised Cylinder Head Bolt Torque Specification and Tightening Sequence for 1994-2002 GM 3.1L and 3.4L Engines

This bulletin is a clarification of the revised cylinder head bolt torque and tightening sequence bulletin.

The updated sequence and specification is as follows:

• Tighten the cylinder head bolts to 44 ft.lbs (60 N-m) in the order
shown in illustration. Use the J 36660-A torque angle meter in order to
rotate the cylinder head bolts an additional 95 degrees.

Please note that 95° is just a little more than a 1/4 turn, not 1/2 turn, or
from 12 o’clock to 3 o’clock on the dial. Do not tighten beyond this
specification, otherwise the bolts will be overstressed and the gaskets
may suffer damage.

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.

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