No, that one is internal under the oil pan and causes lifter ticking and oil starvation to vital parts of the engine. You take the oil pan off and it seals the oil pickup tube to the oil pump. It looks difficult, but really is not if you take your time, most of the Tahoe is really well engineered, so tuff but not impossible. Think of a cracked straw in your drink...same concept, they just get old and brittle.
There are a couple common leak spots...rear main(check by taking off little round plug on bell housing and seeing if oil is all over in there. Up high behind the intake manifold is the cam sensor and oil pressure sender (leaks through the plug itself or the threads) it can leak quite a bit(only buy GM sensors I have seen new other ones leak brand new) and of course valve cover gaskets. There are a few others, but those I seen the most.