I went through installing CARB compliant converters for my Ranger starting 2-3 years ago. It appeared Walker had the best after market ones and OEM is non-existent. I found the Walker system used thinner wall pipe than OEM and was noticeably lighter. It was not a perfect fit, but was close enough that it fit with a little help of some leverage.
Unfortunately, the hanger between the two main cats that connected to the transfer case was poorly designed. and the hanger broke out of the pipe leaving a big hole in the pipe and a loud exhaust. It was replaced under warranty, but that broke again the same way. I got another one under warranty and the way the hanger was attached to the pipe had changed. I still did not trust it and made a stainless steel strap to wrap around that area to reinforce it. I took it to a muffler shop to weld the strap in place. It has been working well for over a year now.
The other problem I had was when the hanger broke out of the pipe the second time, I was on an off-road trip and had to drive at least 50 miles off-road to get to a place for a temporary repair. Then I had to drive about 900 miles to get home to do a permanent repair. When I was replacing the main cats, I discovered the Y pipe had cracked up near the exhaust manifold connection. Apparently, the movement of the exhaust system from the hanger being broken while driving off road cause to much stress on the Y pipe causing it to crack. I think if the wall thickness of the pipe was similar to OEM, it would not have cracked.
It took more than 6 months to get reimbursed for the last failure. Walker would not even reply to my request for warranty coverage. I finally contacted CARB and was able to get in touch with someone that could put some pressure on Walker. Initially, it did not help much, but I kept working with CARB and they apparently found a way to get Walker to listen. I did eventually get reimbursement.
Unfortunately, I don't think you can find a better CARB cat system for a Ranger than Walker. I may have just had bad luck but I hope to neve have to deal with it again, I bought mine through Rock Auto and that was part of the warranty issue. Twice they were out of stock and wanted to replace with a poorer quality unit. Walker was also on back order and had no replacement units. If I had gone to a authorized Walker installation facility the warranty replacement issue may have gone better. Then again maybe not.
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