Anyone remove the catalyst from a Cat C-7?

you may need someone to adjust the computer, to get the truck to run properly if it's removed...
if you are required to have emission testing, it will fail the visual test..
and i would defiantly have a heat shield installed between that pipe and the floor of the vehicle, including the storage areas.. it's not a pleasant thing to have your trip spoiled due to a fire...

Being in California, most likely that's a no-go. In fact, that may be the only reason yours came with a cat in the first place.

I don't believe that they have yet instituted smog tests on large motor-homes in California. I would definitely hold onto it, in case they did. I do know that it wouldn't make CARB happy, but only bicycling makes them happy. I appreciate your comments though.

I am by no means the exhaust police- just understand the consequences and expect the next purchaser if a dealer to require a signed statement that the emissions systems are intact. That's becoming common.

Longroad wrote:
I noticed that my new to me RV has a catalyst exhaust, I was just wondering if anyone has ever removed one a replaced it with a standard exhaust. It is a 2005 C-7 350hp. I noticed that the thing must have gotten hot at one point since the adjacent basement storage has melted carpet. I have placed some heat shielding there, but maybe removal of the catalyst may make that problem a thing of the past and maybe even let the engine breath a little better.
Thanks

my friend has a 2005 C7 and it has nothing of the sort on it? I thought the first years of the catalyst stuff stared on late 2007 models (at least cummins did)

It is not a DPF, just a catalyst muffler. DPFs were required on all 2007+ motors.

Longroad wrote:
It is not a DPF, just a catalyst muffler. DPFs were required on all 2007+ motors.

right gotcha now
understood

Thanks

Longroad wrote:
I don't believe that they have yet instituted smog tests on large motor-homes in California. I would definitely hold onto it, in case they did. I do know that it wouldn't make CARB happy, but only bicycling makes them happy. I appreciate your comments though.

Dealers are not supposed to work on vehicle's with modified exhausts, so if you ever had a break-down, they could suspend repairs until the exhaust system is repaired. That's how its supposed to work anyways. Smaller independent shops might not raise a fuss. A certified CAT dealer probably would. So... could add some hassle if it ever broke down.

You'll find there is no gain to removing it. The exhaust is designed to flow perfectly well with it and it's not much of a blockage anyway.

carringb wrote:
Being in California, most likely that's a no-go. In fact, that may be the only reason yours came with a cat in the first place.

In CA, the only diesels are annually tested are 14,000 GVWR and under. They do not test the ones over that. I know 'cause I went through all that. Now, there are parts of the country that do test the larger diesel engines, Phoenix and Tucson AZ come to mind. Now, all of this could be wrong but, that's the way it was just a short while ago, when we purchased our '04 Itasca Horizon, 36GD with the C-7 330HP CAT.
And no, it did not come with catalyst in the muffler like other year models did. I removed that monster muffler that came with it an installed what's called the Aero 5050XL Stainless Steel straight through muffler. Now, long story short, I got pretty close to no benefit from doing that expensive change-out. All I got out of it was a noisier motor. What a pain in the a$$.

Anyway, in an '05 model, I'd bet quite a bit that you could hack that catalyst muffler off and install one like mine and, that engine will run just fine. However, I'm certainly no expert on this. If I might make a suggestion, get a hold of Brazels RV in Washington state, and consult them about what you might want to do. They've done quite a bit with the infamous C-7.
Scott