January 4, 2012 By Jim Kerr; Photo courtesy BigInJapan.co The
way cars are put together has changed. Adhesives, plastic clips
and even Velcro have replaced most of the screws and trim nails
used to hold panels together in the past. Bolts, however, are
still used for assembling most of the mechanical components, but
even bolts have changed too. Many engines, transmissions and
even suspensions now use torque-to-yield bolts to connect major
assemblies. Torque-to-yield bolts are exactly what they sound
like. They stretch to the yield point as they are tightened.
These bolts are commonly used where exact clamping loads are
required on parts. You may find them used to hold cylinder
heads, connecting rods, crankshaft main bearing caps, flywheels,
front engine dampers, steering knuckles and transmission pumps.
When a shop manual indicates that a bolt is to be discarded and
new ones used, they are almost always torque-to-yield bolts.
Buying new bolts every time one is removed seems expensive and a
waste of time. After