where and how do i replace the o2 sensor in a '99 durango with 5.9L 4x4? limited tools unfortunately.

 

Welcome to D.Forum.

 

Welcome to the site. I will move this thread to the first generation Durango section,
FF

 

which one? you will need a wrench and the replacement sensor, and it is on the exhaust pipe, the pre-cat(used for the a/f mixture in open loop, or warm engine conditions) is between the y-pipe and the cat and the post cat (emissions only) is right behind the cat

 

thanks! if i hollow out the catalytic converter will the rear sensor trigger or will it learn?

 

It will trash it. Don't.

IndyD

 

yup +1