Rocker Arms

This article has been updated with TSB No. 57-61-35

Figure 1 - roller rocker arm:

Figure 2 - conventional ball and pivot rocker arm:

Approximately 4000 1995 A/N cars were built with roller rocker arms. All other 1995 3100 V6 engines were built with the conventional ball and pivot type rocker arm. For 1996 the 3100 V6 engine can be manufactured with either roller rocker arms or ball and pivot type rocker arms. Figure 1 shows a roller rocker arm as compared to Figure 2 which shows a conventional ball and pivot rocker arm. You should not mix rocker arm types on the same engine. It will be necessary to determine which type of rocker arm design the engine was manufactured with when servicing the cylinder head valve train components.

ROCKER ARM AND PUSHROD






REMOVE OR DISCONNECT

1. Valve rocker arm cover.
2. Bolts.
3. Rocker arms.
4. Pushrods. Intake and exhaust pushrods are different lengths with the exhaust pushrod being the longer of the two: intake pushrods are 144.18 mm (5.68 inches) long, exhaust pushrods are 152.51 mm (6.0 inches) long.
^ Use care when removing pushrods so they do not fall down into the lifter valley.
^ Place rocker arms, bolts and pushrods in a rack so they can be reinstalled in same locations from which they were removed.

INSPECT
^ Rocker arms (131) and balls (132) for wear at rotation surfaces.
^ Pushrod (129) ends for wear.
^ Pushrod (129) for bends.

INSTALL OR CONNECT

IMPORTANT
^ When installing rocker arms, bolts and pushrods, coat their bearing surface with prelube, GM P/N 1052365 or equivalent. Install these components in the locations from which they were removed.

1. Pushrod.
^ Intake pushrods are 144.18 mm (5.68 inches) long.
^ Exhaust pushrods are 152.51 mm (6.0 inches) long.
^ Make sure pushrods seat in lifter.
2. Rocker arms.
3. Bolts.

TIGHTEN
^ Bolts to 14 Nm (124 lb. in.).
^ Turn bolt an additional 30 degrees.

4. Valve rocker arm cover.