My question is about the cat converter. I brought my car to a local repair shop, same shop i've been bringing it to for years, had the front and rear differential replaced. A week of two later on of the 02 sensors goes out. They replace that but recommend that i replace the other 3 as well. Couldn't afford it at that time. Well, 2 weeks later, as i'm getting on the highway the jeep would get past 20 mph and was losing speed. I pulled over, let it sit for a bit and tried to get to the nearest off ramp - no luck. I wouldn't accelerate past 5-10 mph. Called AAA, had it towed to the same shop and waited at home for the call. They finally call later that afternoon and tell me the catalytic converter needs to be replaced and i may very well need to replace everything from the cat to the tailpipe! They quote $1500-$1600, could be more. They say they don't understand how the cat went so quickly after just having replaced the 02 sensor. I told them I did notice the jeep was going through gas like crazy and they said that explains why the cat was so damaged. Gas likely got in the cat and not sure what further damage there might be. My question, does their statement of needed work/repairs and quote sound accurate? Do I really need to change everything from cat to the tailpipe? Does $1500-$1600 sound inflated or on par for emissions-type repairs in the state of MD? I've invested so much already in this jeep, which i love, that I just don't know if it's worth the additional investment. Thank you in advance for any guidance and/or advice you may be able to offer.