GM 15809057
Inlet Pipe

The oil cooler which can be unitized with Radiator or installed separately in front of the Radiator are serviceable cooler lines and hoses. To replace Engine Oil Cooler hose/pipe, first the remove the plastic caps from the quick connect, pull them back from the pipe. Hold one end of the retaining clip and use a small pick type tool or bent screwdriver to pry the other end free from the quick connect fitting, then rotate and pull the clip off and discard the old clip. For a 6.0l engine, detach from the clip hose for the oil cooler that is located on the lower concealing fan; pull back the hoses but pull the pipe fittings straight out of the q/c fitting in the Radiator. Lift the vehicle, and detach the Exhaust Manifold pipe nuts and relocate the pipe. An 8.1l engine, remove the oil cooler hoses from the clip, and pull the pipe fittings straight out from the Radiator quick connect fittings, then raise and support the vehicle. If equipped, take off the engine shield bolts and the shield. For a 6.0l engine, unscrew the Oil Cooler Hose bracket bolt and the Oil Cooler Hose adapter bolts, sliding off the hoses assembly and replacing the gasket, tossing it aside to inspect the fittings and hoses for damage. In the case of an 8.1l engine, the instructions are as follows: use an allen wrench to remove the bolt for the hose bracket; remove the quick connect fittings at the engine and the hose assembly; discard the gasket and inspect for damage. While installing confirm a snap can be heard when the tube ends of the hose assembly are connected to quick-connectors and the full insertion of the tube can be checked by pulling forcefully. For an 8.1l engine, the quick connect fittings at the engine are connected, the hose bracket bolt is installed, and tightened up to 50 nm (37 ft. Lbs). For a 6.0l engine install hose assembly with a new gasket with tightening adapter bolts to 12 nm (106-inch lbs.), bracket bolt to 25 nm (18 ft. Lbs.). If so provided, mount the engine shield and bolts which you tighten to 20 nm (15 ft. Lbs.) in torque. Place the new retaining clip on the quick connect fitting, making sure that it bites into all the slotted areas: leave this to twist all the way until it locks in place allowing the ears to be visible and the clip to be mobile. Mount a new retaining clip into the other fitting; connect the pipe to the Exhaust Manifold and tighten the nuts to 50 nm (37 ft. Lbs.). Lower the vehicle, then for a 6.0l engines, connect the hoses to the hose clip on the Fan Shroud and push it closed. Put on a plastic cap at the end of the oil cooler line which goes to the quick connect fitting. If damaged or lost, get a new cap prior to installation. For 8.1l, attach the hoses to the clip, connect to the Radiator and pull back sharply to ensure the line enter the fitting until you hear or feel a click. Finally tighten the snap of the plastic cap onto the quick connect fitting ensuring that there is no gap between them.

Connect the quick connect fittings at the engine, install the hose bracket bolt, and tighten it to 50 Nm (37 ft. lbs.).

Snap the plastic cap onto the quick connect fitting, ensuring it is fully seated with no gap present.

Connect the quick connect fittings at the engine, install the hose bracket bolt, and tighten it to 50 Nm (37 ft. lbs.).

Remove the oil cooler hose bracket bolt, disconnect the quick connect fittings at the engine, and remove the oil cooler hose assembly, discarding the gasket and inspecting the fittings, connectors, and hoses for damage.

Tighten them to 100 Nm (75 ft. lbs.).

Install the hoses to the clip, connect the lines to the radiator, and ensure the line is fully inserted into the fitting until a click is heard or felt, pulling back sharply to confirm proper installation.