GM 12576628
Rocker Arms

The procedure starts with left or right valve rocker covers removal before bullens are taken out along with the push rod against potential loss into the lifter valley. First remove the Rocker Arm bolts and discard them while organizing all valve train elements on a rack according to their original positions before carefully removing the pushrods to avoid accidental fall into the lifter valley. Complete the valve Rocker Arm removal process by taking away the rocker arms together with pushrods. The Pushrod installation begins by applying prelube gm p/n 1052367 (Canadian P/N 992869) or its equivalent to the Pushrod ends where the length of the intake rods matches 144 mm (5.68 inches) while the exhaust rods extend to 152.5 mm (6.0 inches). Reinstall pushrods together with rocker arms to their initial positions and replace each bolt with a new one. Use the torque angle meter (J 36660-A) to apply an additional 30-degree rotation of bolt torque to 14 nm (124 in. Lbs.). As a concluding step you need to install the left or right valve Rocker Arm covers.

The initial step before valve Rocker Arm and push rod replacement starts with removing valve Rocker Arm covers followed by segregating all components to maintain correct later installation. You should begin by removing the Rocker Arm bolts before extracting the rocker arms as well as the pushrods. Start by repositioning the pushrods to their installation locations and ensure the ends receive application of gm p/n 1052356 chemical or its substitute material. The intake pushrods have yellow stripes for marking and measure 5 3/4 inches while exhaust pushrods with green stripes measure 6 inches in length and need to properly seat in the lifter. Next install the rocker arms before affixing Rocker Arm bolts at 32 nm (24 ft. Lbs.) while replacing valve rocker covers.

Begin service and repair procedures for the Rocker Arm assembly using torque angle meter (J 45059) as the main tool. The first step of removal involves removing the valve Rocker Arm cover together with the Rocker Arm bolts. Begin the service by first removing both pushrods and valve rocker arms. Begin the installation process by applying engine oil supplement (EOS) gm p/n 12345501 (Canadian P/N 992704/88862586) or an equivalent product to the ends of the push rods. Keep in mind that the intake valve push rods extend to 144 mm (5.75 inch) while the exhaust valve push rods reach 152.5 mm (6.0 inch). Insert original push rod positions after applying engine oil supplement (EOS) gm p/n 1052367 (Canadian P/N 992869) or an equivalent oil to the Rocker Arm friction parts. Fasten valve Rocker Arm bolts to 32 nm (24 lb ft) and put the valve Rocker Arm cover back.

Replacement of valve Rocker Arm and push rods requires initial removal of valve Rocker Arm covers before separating components for their correct installation sequence. The proper replacement process involves starting with bolt removal from the rocker arms followed by extracting both components and then the pushrods. Following original placements install the pushrods with gm p/n 1052356 lubricant or its equivalent on the ends. The intake pushrods show yellow stripes to indicate their 5 3/4-inch length while exhaust pushrods have green stripes at 6 inches; proper seating must occur for both types of pushrods in the lifter. The next steps should be installation of Rocker Arm bolts followed by torqueing them to a value of 32 nm (24 ft. Lbs.) and reinstallation of valve rocker covers.

The exhaust pushrods, colored green, measure 152.51 mm (6.0 inch) long.

Confirm that the pushrods are seated correctly in the lifter.

Place the pushrods back in their original locations, coating the ends with Lubricant (part number not specified).

First install the pushrod(s), then the valve rocker arm(s), followed by the valve rocker arm cover(s).

Use compressed air to blow oil out of the tapped holes in the cylinder head, lubricate the ends of the push rods with new engine oil, and install them in their original positions.

Install the push rods in their original locations.

Ensure the pushrods seat properly in the lifter.

Coat the rocker arm friction surfaces with the same prelube.