OK i am going to replace my 02 sensor and i was checking online for some and found a bosh for $30.00 but it has listed a front and a rear 02 sensor the last time i looked i only saw the 1, so are there 2? and if there are 2 where are they at:screwy:

I think there are two, one in the exhaust mainifold and one after the cat.

Front one for 96MY 4.0L XJ is PN:5602 7916
After cat one for XJ 4.0L is PN: 5604 1005

You can download a parts catalog for a 96MY here:
http://www.xjjeeps.com/tech_reference.asp?section=2&ID=0

I got the information from figure 8-605....

there are 2 o2 sensors an updraft and a downdraft... If you go to an advanced auto parts they will scan the computer for you for free and tell you which on it is... I would recommend an oem part becuase I put an after market one in my jeep and it went bad again a short time later... the oem one cost 100 bucks but I have not had a problem with it in over a year... run better and much beter gas mileage... good luck