Catalytic Convertor questions.

[okfoz]

2007 Tahoe LTZ - 5.3 with Flex
I threw a code the other day saying that one of my cats is creating new back pressure... I cleared the code, has not come back... But over the past few years I have noticed a significant drop in efficiency. When I got it in 2014 I could get 18mpg, now I struggle to get 16mpg.

Are there any setups I should avoid, or just some that are better than the others, or does it not matter? Can I just replace the Cats? or do I need to do the entire Y downpipe?

Are there any High performance versions that are really worth it?

thanks.

 

[swathdiver]

2007 Tahoe LTZ - 5.3 with Flex
I threw a code the other day saying that one of my cats is creating new back pressure... I cleared the code, has not come back... But over the past few years I have noticed a significant drop in efficiency. When I got it in 2014 I could get 18mpg, now I struggle to get 16mpg.

Are there any setups I should avoid, or just some that are better than the others, or does it not matter? Can I just replace the Cats? or do I need to do the entire Y downpipe?

Are there any High performance versions that are really worth it?

thanks.

What specific codes were you getting?

Here's my story. Truck ran great, did not feel down on power but mileage was poor. Even had it tuned. Then cat code(s) started showing up. Turns out one of the cats had been cut out and replaced and it was this very cat that was failing again. Bought Magnaflow 51578 from Got Exhaust which is a vendor here, beat a competitor's price, and mileage was restored. It also looks great and the motor picked up a little power, the design of the pipes is much improved for flow. Still running stock exhaust.

If you go this route, keep your purchase papers and sell your old cats to the local scrap yard, you'll be surprised how much they're worth.

 

[okfoz]

I did not write down the code (I really should have)... I will wait to see if it comes back... I have suspected a Cat problem for a while...

John