Factory CAT Questions
 

I have a piece of 4" exhaust pipe, what size is our factory exhaust? I measured the tailpie and its 4" but it looks like it flares out, is our factory exhaust only 3"?
If I cut the cat out will the 4" Piece of pipe I have work? What other precautions do I need to take? Do I need to unhook my batteries before hand? Will it through a code if I don't?
Thanks!!

2007 5.9l cummins.

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anyone??

for working on the exhaust they recomend you do disconect the battarys but i never did while puting my stacks on, also the stock exhaust is 3" from turbo down into a four inch tip. if you have a 4" pipe already it will not work it is to big, unless you buy two bell reducers from 4" to 3" but i recomend buying a new 3" pipe to replace it. Also on mine i have the stock down pipe into 5" flex tubing all the way to my stacks

sorry but that's not entirely correct, as of the 600 models, they came with factor 4 inch exhaust.

the best way to find out is to measure the pipe and go from there

indeed it is. I know my 04.5 so doesn't have a "tip" it's 4 inch all the way to the tailpipe, then again I don't have a cat either.

i took both the cat and muffler out of mine and ram 5" flex all the way to my stacks

was yours a cali truck? I have a resonator...but not kitty

no made in michigan but stayed in idaho ever since

that's strange...

why is that strange