Cat c13-525 Exhaust modifications

[Paul Champagne]

Hello All

Just wondering if anyone has done any air filter and exhaust mods to their Cat C13 -525 engine? If so did it improve the torque and mileage as I am averaging only 5.8 mpg at 60 mph in my Thunder also seems to be lacking in power...

Any suggestions or comments would help

Thanks

Paul

[Gerald Farris]

Paul,
Monaco did not equip all C-13s with the same intake systems. Your question can be answered more accurately if you give the year model of your coach.

Gerald  

[Paul Champagne]

Hi Gerald

Model is 2006 Patriot Thunder hope that helps  44ft 11'

Thanks

Paul

[Michael Marcocchio]

Hello when I bought my new to me 2005 Thunder couple years ago it came with a modified air intake system and a high performance muffler. Power seems good mileage is little low in 6 MPG range.   from what I gather from previous owner that intake and muffler did make unit run and increased power. After I changed to a new clean air cleaner I got another MPG so I getting around 6 or so MPG but we are heavy big power and we get what we get..

[Gerald Farris]

Paul,
The intake system on the 2005 Thunder was badly undersized. However, from what I understand about the 2006 model Thunder, the intake system was adequate with the exception of the air cleaner itself. The most common correction for this problem is to use the air cleaner from the 2007 Marquis with the C-15 engine.

The exhaust system on the C-13 has the same problem that the exhaust on all coaches has, it has to be somewhat restrictive to quiet the engine down to the level that luxury coach owners expect. A straight through design muffler will give you a little better performance and slightly better mileage, but the increase in engine noise, especially with the Jake Brake on, may be more than some owners will accept.

Gerald  

[Jeff Watt]

Gerald,

Is this a direct swap or does there have to be some modifications to use the c15 filter?

I too think there is too much restriction as i just changed my filter after 8k miles put in a new one and the gauge shows it half.

Jeff

[Gerald Farris]

Jeff,
I think that it takes very little if any modification to the intake system on your coach to go to the C-15 filter, but I am not sure. Maybe an owner who has made the change can answer the question, or I will research it next week and get back to you.

Gerald  

[Jeff Watt]

Thanks Gerald,

Can someone  with a c15 in a 06 and newer Coach provide the air filter part number. I should be able to look up and see what differences there a between the c13 and the c15 filter.

As a side note, the air filter on the 05 is the same on as on the 07, significantly easier install though.

I thought it would be easier to research this on the web and while I can get a lot of info, not the exact info I need. The Donaldson site is too large with too many variables to get the right match.

Jeff

[Paul Champagne]

The mechanic at Redland RV Performance suggest I change my exhaust from 4 : to 5" and also change to the new style K&N HIGH FLOW AIR FILTER will improvr torque and supposedly better mileage  not sure if will here the increased noise in the Coach that's what I am concerened about...

[Jeff Watt]

I posted the query on the diesel forum (used to be CatRV) and Brett Wolfe mentioned that a better filter from different (larger) motor is a good option. He also suggested to look at the space available and maybe there is a better filter combination available that OTR trucks may be using. He mentions to also look at the piping from the inlet to the filter and from the filter to the turbo. Maybe this a project to delve into when I the MH will be sitting for a few months, I.e. latter this winter once I am down south. Need to check out the other park residents to see if there are any ex-cat engineers  

Paul, others with far more knowledge than I may chime in, but from what I have read K&N get more flow because they have a larger micron opening, thereby possibly letting in more dirt - not a good thing. Maybe their newer filters are better?

Jeff

[Jim Nichols]

I only have a C-9 but  I have seen changes on the larger engines go with a larger diameter filter. They had to modify the two brackets by extending the straps.  Beaver owner Dale Elly made that change to his 45' Marquis and claimed he could go farther climbing a hill before it down shifted. Not sure if he is still active as he had to to go back to work. I also had to modify my intake but I went overboard and I am very happy.

[Paul Champagne]

Ok I went with the 5" exhaust and K&N air filter on my Coach last spring and it does make a little difference on my 06 Thunder especially with the Jake on it is louder but not loud enough to bother you in the Coach, as far as performance it is better on the hills but still could use a performance chip for those long steep grades. The mileage up and down I5 is just under 6 mpg at 60 mph so happy that I did the change.

Thanks

Paul

[Lee Welbanks]

My coach already has 5" exhaust and am thinking about going to the C-15 air filter and clean up the intake air box a little. I would not run a K & N filter on anything. Contrary to what KN says they pass way too much dirt. Cat will run you off if you show up with one of these filters.
Now I get 6-6.5 mpg.

Attached filter test report.
http://www.nicoclub.com/archives/kn-vs-oem-filter.html

[Keith Moffett]

While at Brazel's Performance RV in Centralia, Wa we met a fellow RVer who was  having the performance chip put in his DP 40 ft. with 3 slides.  After this he did the Alaska trip and was amazed at the MPG and performance increase.  I had a chance to follow him in our SUV for some distance and I must say....'dang".  I had to work tokeep up.
I do believe that improved air in and exhaust is a good first step.

[Paul Champagne]

Further to Lee's comments on the K&N Filters for the RV Diesel industry their filters do not require oil see comments from K&N Website

A Washable Heavy Duty Air Filter
 K&N has developed a line of washable commercial grade air filters designed specifically for large turbo diesel engines, class 6-8 over-the-road trucks, agricultural and earth moving equipment, and diesel motorhomes. Built with the unique characteristics of turbo diesel engines in mind, these air filters do not require the use of oil and can be easily cleaned with power sprayers or commercial parts washers. The filters are also designed to provide lower restriction and higher air flow, while delivering exceptional filtration efficiency, and extended service lives.

Washable and Reusable
 K&N HD air filters can be easily cleaned and reused to reduce the cost of replacing air filters. These "depth-loading" air filters feature our washable "lofted" hybrid air filtration medium. They do not require any oil and are robust enough to be cleaned with pressure washers and standard truck washing equipment. Most other heavy duty air filters are built into the canister as a complete non-serviceable unit; the filter and canister must be replaced dirty at the end of a single service interval. A K&N reusable HD filter will reduce the cost of buying disposable filters and canisters over and over. Perhaps even better, when restriction builds beyond a desired level, just wash the filter. So instead of short cycling expensive disposable air filters, keep restriction down and horsepower up with K&N.