There are four in total. One before and one after the catalytic converter on each side of the engine.
Yes.
oneone
Two.
Yes, you unplug and unscrew them.
They are screwed into the exhaust on the rear of the engine.
A 2002 Chrysler Town and Country has two oxygen sensors.
Oxygen sensors are screwed into the exhaust on both sides of the catalytic converter.
No O2 sensors on a Cummins until the 2007 6.7L
Four. Two forward of the cat converter and two aft.
the upstream O2 sensors, are located on the top of the exhaust manifolds. they are sitting right there in the open where you can see them.
Assuming you have the V-6 engine, it has two downstream (after the cats) O2 sensors and two upstream (before the cats) Air/Fuel Ratio Sensors. So the answer to your question is two O2 sensors.
there are 4 O2 sensors on a 2007 Yukon. 2 on each side. upper bank is on the down tube of the exhaust prior to the catalytic converter, lower bank is after the catalytic converters