o2 sensors...

So i picked up a new cat at AutoZone today because mine had rusted apart after 206000 miles, and realized that i probably need a new o2 sensor. But, please explain to me what the difference is between a universal 8 dollar o2 sensor and the one they tried to sell me for 75 bucks?!?!?

Heated (which some of these take) and Non-heated (which some of these don't take)....

Also the $8 O2s has no connector, you would have to wire the thing, which is a PITA to do. If you get the connections wrong or not good enough there are problems.....

I would love to hear a lot of details about O2 sensors.

I have 3-4 of the 4 wire ones laying in my tool box. A buddy told me that unless the part numbers match, I couldn't use them on my car. Saying the "range" measured on one sensor might be different on another and still have the same wiring and screw thread.

I kinda thought that was crazy given the generic sensors.

I know there is 3 and 4 wire sensors and I believe the generic one I saw had a single wire..can't remember for certain though.

02 sensors are an item where you do get what you pay for. Stay away from the cheap charlies and buy a good quality OEM style sensor from a reputable company. They are plug and play and are specifically designed for your vehicle!

X2!! I think Bosch supplied the O2s for the older XJ's. maybe the newer one's too.....