My 2000 LS400 is originally from California, but now no longer in California.

Can I replace the failed catalytic converters with regular 49-state converters?

Asking about technical compatibility, not about legality.

Thanks very much.

 

from my limited experience a non-CA cat should fit the same. the CA cat just has stampings on them to show CARB (california air resources board) compliance per the regulation. our smog guys actually verify these numbers and cross check them (at least good smog guys do).

btw, the LS400s cats rarely fail esp later models like your 2000. what makes you think it's your cats? i ask bc in most cases the O2 sensors are reading improperly or there is a crack in the system to throw a CEL for cat inefficiency.

 

No CEL, but there seems to be a rattle from the front exhaust when throttle applied.

 

check your heatshields!

 

Good idea. Many thanks.