i talked with the guys at LC Engineering months ago and they told me the first thingy (from the engine side) is a resonator and the next is a cat. you could take the first off but it would make it louder. the cat you don't want to mess with period. nothing but probs and no significant gains at the revs you would use your truck at (2000- 4000). get a header and a performance muffler or cat-back and you will see some nice improvement. i have the 2.7 and replaced the muffler with a dynomax super turbo and it was great bang for buck. good luck.jerseytaco said:hello all im new here and had a question about replacing my exhaust. I have 2000 2.7 litre extra cab it looks like it has two cats but im not sure? sounds stupid huh? but does any one know or can anyone tell me if it does? also if it does have two can I replace it with only one? thanks for your help.
Yes they're both cats and yes, you do need both cats. Your ECU is programmed to compare the signals from the two O2 sensors for catalyst efficiency. Without one of the cats you'll trip the P0420 code for catalyst efficiency threshold exceeded.jerseytaco said:hello all im new here and had a question about replacing my exhaust. I have 2000 2.7 litre extra cab it looks like it has two cats but im not sure? sounds stupid huh? but does any one know or can anyone tell me if it does? also if it does have two can I replace it with only one? thanks for your help.
i called three different parts depts for toyota and one was'nt sure but the other two said they were cats. i guess the guy a LC engineering did'nt know what he was talking about.jerseytaco said:
