I have an 03 chevy 2500hd with the duramax and allison. i recently replaced the water pump but i must have not properly

if that cooler will slide back enough once unbolted off the block then it can be slid out but that is just a tough area to do this in

it takes 2.5 hours to r& r the adaptor but yes it can be done that way

Removal Procedure

1. Drain the engine coolant and the engine block.

1. Remove the oil pan skid plate bolts and plate.

1. Remove the crossmember bolts and crossmember, 2-Wheel Drive (2WD) vehicle shown.

1. Remove the crossmember bolts and crossmember, 4-Wheel Drive (4WD) vehicle shown.

1. Remove the oil filter.
2. Remove the left front tire.
3. Remove the left fender wheelhouse inner panel.

1. Remove the water pump outlet pipe nuts from the water pump.
2. Remove the engine wiring harness retainer from the inner stud.

1. Remove the oil cooler adapter nuts from the flywheel housing.
2. Remove the oil cooler adapter bolts from the oil cooler adapter and the oil cooler.
3. Remove the oil cooler adapter.

1. Remove the oil cooler bolts.
2. Remove the oil cooler with the water pump outlet pipe.
3. Remove the oil cooler O-ring seals.
4. Remove the water pump outlet pipe from the oil cooler.
5. Remove the water pump outlet pipe O-ring.
6. If required, clean and inspect the oil filter adapter/oil cooler.

Installation Procedure

1. Install NEW O-rings to the oil cooler.
2. Install a NEW O-ring onto the water pump outlet pipe.
3. Lubricate the O-ring with engine coolant.
4. Install the water pump outlet pipe to the oil cooler.
5. Install the gasket for the water pump outlet pipe on the water pump.
6. Install the oil cooler.

1. Install the oil cooler bolts. Tighten the bolts to 21 Nm (15 ft. lbs.).

1. Install a NEW seal in the coolant duct to the flywheel housing.
2. Install a NEW gasket for the coolant duct to the oil cooler.
3. Install the nuts for the coolant duct to flywheel housing.
4. Install the bolts for the coolant duct to oil cooler. Tighten the bolts/nuts to 21 Nm (15 ft. lbs.).

1. Install the engine wiring harness retainer on the water pump outlet pipe to water pump inner stud.
2. Install the water pump outlet pipe nuts. Tighten the nuts to 25 Nm (18 ft. lbs.).

1. Install the oil filter. Tighten the oil filter to contact plus 1 to 1 1/4 turns.

1. Install the crossmember and bolts, 4WD vehicle shown. Tighten the bolts to 100 Nm (74 ft. lbs.).

1. Install the crossmember and bolts, 2WD vehicle shown. Tighten the bolts to 100 Nm (74 ft. lbs.).

1. Install the oil pan skid plate and bolts. Tighten the bolts to 20 Nm (15 ft. lbs.).
2. Install the left fender wheelhouse inner panel.
3. Install the left front tire.
4. Lower the vehicle.
5. Fill the cooling system.
6. Inspect the engine oil level and add as necessary.