I need to replace the whole thing from the manifold back to the muffler on a 2002 volvo s80...does anyone know if it requires welding, and how much??? Thank you!

 

If you buy OEM parts no welding just bolts up.

 

How many miles on your 02? an 02 is covered by emissions warranty for ECU and Catalytic Converter for 8 years. I just had mine replaced under warranty last week for my 02 T6. Also replaced the fuel pump under warranty also.