Sorry if this has been asked a bajillion times on here, but I looked on google and still couldnt find my answer. Im thinking about doing some exhaust work soon on my truck and will involve the third cat delete, I just dont know the size of the pipe that goes into the third cat. Is it 2.5" or 3"?

 

Crawl under there, wrap a string around it, mark where the string does the whole wrap, crawl out from under there, measure the distance, and divide that by 3.14 .

That'll give an answer close enough.

RwP

 

That'll actually work? Ive never known how to measure the diameter without just cutting it up. I was never much at math, so thanks for the help!

 

I am pretty sure it's 2.5

 

I just went to Auto Zone online and put in the spec that you have at the bottom of your profile and it came back with 2 CA type cats and one normal on. Both inlet and outlet were 2.5 inch. I use this method checking different places for the sizes. Hasn't failed me yet. Bit I am to old to climb underneath the truck.

 

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Im not toosure on size. I thought it was 2.5 but I always cut it apart where i need when I redo a exhaust. Take all the pieces with you and lay it out . U might need adapters and clamps. Or a pieces of pipe . Saves you multiple trips to the auto part store. I just put a new one in my 5.9L ram. Dumped it out before the axel and had to move the muffler about a foot forward . I needed alot more then I thought. Multiple adapters. But. Since It's already off the truck I got good welds on everything and had all of it done before i put it up in the truck...then just had to put 1 clamp on the very front piece