How to Change the Oxygen Sensor on a 2005 GMC Savana Van 3500

GMC released the full-size Savana van in the 1996 model year as the replacement to the aging Rally Wagon. The 2005 GMC Savana 3500 came standard with a 6.0-liter engine that cranked out 300 horsepower and 360 foot-pounds of torque, so it could handle heavy loads. A set of four oxygen sensors monitored the exhaust as it exited the engine and after it passed through the catalytic converter. These sensors would measure the amount of oxygen in the exhaust to determine if the engines air-to-fuel ratio was correct and if the catalytic converters were operating correctly. Replacing a failed oxygen sensor on the 2005 Savana 3500 is a straightforward task that almost any DIY mechanic can complete.

Instructions

Park the Savana on a flat surface and let it sit until the engine is cool to the touch. Allow the van to sit for an additional hour, so the exhaust can cool.

Kick wheel chocks behind the rear wheels. Lift the front of the van with a floor jack and slide jack stands under its frame rails. Crawl under the front of the vehicle until you have a clear view of the front-most exhaust pipes that connect to the exhaust manifolds.

Find the oxygen sensors on the front-most exhaust pipes, just after the exhaust pipe connects to the exhaust manifold. The bank No. 1, sensor No. 1 is on the drivers side and bank No. 2, sensor No. 1 is on the passengers side.

Trace the failed oxygen sensors wiring until you reach where the sensors harness plugs into the Savanas harness. Unplug the oxygen sensor harness from the Savanas harness.

Remove the failed oxygen sensor, using a ratchet and oxygen sensor socket.

Apply a thin coat of an anti-seize compound to the new oxygen sensors threads and hand-tighten it into the exhaust pipe. Tighten the sensor to 31 foot-pounds, using a torque wrench and oxygen sensor socket.

Reconnect the oxygen sensors wiring harness. Lift the van off the jack stands and lower it to the ground.

Park the Savana on a level surface and allow it to sit until the engine is cool to the touch. Let the van sit for another hour to allow the exhaust to cool.

Wedge wheel chocks behind the rear wheels. Raise the front of the van with a floor jack and slide jack stands under its frame rails. Lower the van onto the jack stands. Crawl under the center of the van until you have a clear view of the two catalytic converters there is one on each pipe.

Find the two oxygen sensors, there is one screwed into each pipe, just after the catalytic converter. The sensor closest to the front of the van is bank No. 2, sensor No. 2 and the one closest to the rear of the van is bank No. 1, sensor No. 2.

Trace the wiring for the failed oxygen sensor upward until you find where it connects to the vehicles wiring harness. Unplug the sensors harness.

Remove the oxygen sensor, using a ratchet and oxygen sensor socket.

Apply a coating of an anti-seize compound to the replacement sensors threads and thread the sensor into the pipe by hand. Tighten the sensor to 31 foot-pounds, using a torque wrench and oxygen sensor socket. Connect the sensor's wiring harness into the Savana's wiring harness.

Lift the vehicle off the jack stands, remove the jack stands and lower the Savana to the ground.