How to Replace the Oil Cooler Line in a 1997 Yukon

The 1997 GMC Yukon uses an oil cooler, which is an integral part of the radiator. The passenger side of the radiator has cooler lines inside the radiator tank for the transmission cooler. The driver's side also has internal cooler lines to cool the engine oil. The cooler lines come from an adapter on the block to another block close to the bumper. The cooler lines are attached to this block and run to the driver's side of the radiator. The oil cooler fittings are held into the radiator with the use of spring clips.

Instructions

1

Raise the front of the Yukon with the floor jack and place jack stands under the frame. Lower the truck to rest on the stands. Remove the skidpan under the radiator and front of the engine using a socket and ratchet.

2

Place the drip pan under the oil cooler block located close to the bumper. Follow the oil lines from the driver's side of the radiator down to where they connect to the oil cooler block. Remove the 13 mm bolt in the middle of the oil cooler line block, that secures the oil cooler lines to the block, using a socket. Pull the hose block off and hold it down into the drain pan.

3

Remove the oil lines at the radiator by prying the spring clip out of its pocket using a screwdriver. These clips are C-shaped springs and fit into three rectangular grooves in the radiator side oil cooler fitting. The oil cooler line end fittings have a flare, which snaps behind the radiator fitting spring clips.

4

Rotate the oil cooler fittings using a 7/8-inch wrench. At the same time, pull the fittings straight out. Check the old cooler lines to see if the end that connects to the block has gaskets on each of the hose ends. Look at the new lines and compare them. If the old gaskets are stuck to the block, remove them with a screwdriver. Install the new gaskets on the new oil cooler line ends if they are not already installed.

5

Install the oil cooler line block and tighten the 13 mm bolt. Push the spring clips on both radiator cooler line fittings. Make sure the clips are in the slots on the radiator side cooler fittings. Twist and push each cooler line fitting into the radiator side fitting until they give a click as they seat.

6

Install the lower skid plate and tighten the bolts. Raise the truck with the floor jack and remove the jack stands. Lower the truck to the ground.

7

Start the engine and allow it to run for just a short period of a few seconds and turn the engine off. Check the oil level with the dipstick and add some oil as necessary to bring it up to the proper level. Removing the oil lines only looses a pint or less of oil.