I was going to order a replacement cat of my 05 Lariat from Magnaflow. At their website I found the 94136 and 94136CA. What is the difference? I could find or see any difference in their product listing. Also, if I am installing one hi-flow do I need to change the other one to a high flow also? I am only getting a CEL for Bank 2. I am selling the truck so I just want the catalyst system working correctly before I do.

Edit: My 05 has the 2 cat system.

 

I'm not an expert but it seems the ca would be for California emissions as they are much more strict.

 

ca must me oem