What sort of average life should I expect from new catalytic converters?. Just before I bought my 2005 LR3 v8 in December 2023 the dealer had installed new catalytic converters (August 2023). Now it appears that these are no longer working properly after 8,440 miles driven. I am told these were aftermarket cats installed. The dealer is well respected as both a used car dealer and a Land Rover repair shop. The dealer has told me they are contacting the cat supplier, so my fingers are crossed. So I guess I just wait but this problem seems very odd to me.

I am fearful the cat supplier will do nothing. And if that's the case, I honestly don't know what I should do or say. Certainly I need to wait and see what the dealer has to say. Thoughts / suggestions are sure appreciated!

 

I know of no official LR dealer that would install aftermarket cats. Unless factory ones were NLA? Which I can see is possible. At almost 220k miles I am still on factory and no LR3 I have been around personally has had its cats replaced yet. How is the vehicle being driven? If it is used for very, very short trips often that the cats dont get up to temp and can fail. A shop I worked at 20 years ago learned this with a vehicle we bought and never used - we moved it in and out of one of the garage bays almost every day. The cats went out within a few months.

 

I have had multiple in the 200k range with no cat issues

 

What codes are you getting?
I know there are several codes that recommend replacing cats as last option, but other things can usually fix it.
You may have an intake issue causing a lean or rich issue that is giving bad readings to the O2 sensors, or an exhaust leak up stream of the O2 sensors that is changing the gas mixture ratios making the O2 sensors unhappy.

As others have posted 150,000-200,000 is not uncommon. Some go as early as 80,000. A few months is not right.
If you had an issue that pointed to the cats, you replaced the cats, and the problem is back, It most likely is not the cats.

Look deeper for the issue causing the code to point to the cats. By the way, which bank was it saying is bad?

Hope this helps
Jeff

 

I have had the "check engine" light on for literally 4 years because 1 of the cats on my 2007 SE is bad. It went at about 150k miles. The shop said unless it's causing any other issues, it's not a mandatory fix since I'm in a state that doesn't do emissions testing (MN)...so far I've let it go.