Catalytic/sensor Repairs

[Deronh]

Hi everyone,

I just joined the site. I have owned several Toyota 4x4's over the years and have always done my own maintenance/repairs/off-road equipment. I joined because my folks own an '05 GX470 and it's in need of repairs.

They took it in to get looked at and left with a $3,000 estimate. I'm not 100% sure what it covers but they were told that all 4 cats needed to be replaced, 2 up front and 2 in the rear. I don't live close enough to swing by and check things out. The rear ones are making a lot of noise, so they must be broken up inside. I don't know about the front ones. I'm not familiar with their anatomy and I'm trying to figure out if it's a job I could tackle on my own. I have no doubt that all the O2 sensors need replacing and as long as those are within reach I can certaining do it. I haven't yet looked up info as to how many there are. As far as the rear cats are concerned. How are they installed? Are they bolt on that can be removed in sections? Any info or advice is greatly appreciated.