Well i know the advantages of a freer-flowing exhaust system, however my father who owns the truck needs me to convince him that we "need" a 4" exhaust system for our new truck, a 2007 F-350 CC dually Towboss. Towboss it is, i tow almost daily with it, most of the time the trailer is over 10k, however sometimes it can gross out at 16 or 17k pounds. The truck is bone stock as far as performance mods go, aside from EGR unplugged. I do not post here as much but i do know my fair share about the 6.0's, and that they can run near-dangerous exhaust temps while towing heavy loads. I also drive this truck daily and use it as my work truck. I love how opened-up 6.0's sound. I tried to convince him to let the business buy pillar guages, to monitor the temps. His words were- "if the truck needs them, why didn't Ford put them in at the factory?" I am thinking getting the exhaust to lower the temps, not just monitor them and back out when needed. I need the system to be moderate in tone, as he is not all about the rumble and turbine whistle.. However i like the tone when im driving it. I am thinking 4" aluminized, no cat but with muffler. No drone as well. I would want to be able to reinstall the cat for dealer visits but also have the delete pipe. I have been eyeing up the MKO systems on ebay, $350 but they do not have the cat option. Keep in mind that the exhaust will not cost him out of pocket, the business will be buying it, so while price is not a major issue, i do not want to go overboard-$400 or $450. Please help me be a salesman here FTE.

 

OEM exhausts are a compromise, they have to give reasonably good performance, be quiet enough to pass regulations and be cheap to make. I have been told that an exhaust should be no more than 25% increas in size than it is OEM. It will allow the system to breath better particularly if it is mandrell bent as it will not have the restrictions in it that is found with OEM and some other exhausts that are bent on a pipe bender. I put a Gibson turbo back 4" on my 04, pleasant sound, a little better performance and therefore I am satisfied with it. This is a progressive thing, eventually I may get a chip/programer, intake to go with it. Diesel world ran an article on how the various types of changes effect the vehicle. 17 MPG stock and eventually they were in the 20's with minor changes to intake, exhaust, lubricants.

But first and formost it is a personnal thing you have to want it to realize its benefits, so in reality I dont know how you will convince your dad, but wish ya luck in it.

 

strokin_it7.3,

Yes the larger exhaust will lower the EGT's some which is a benefit. Your dad is looking at cost analysis of benefit vs. cost as a business man. IMO you need to install at least and EGT gauge first and formost to monitor temperatures. FMC chose the boost gauge over the EGT gauge and only have so much space in the IC to put gauges. They also make all there other gauges just glorified "idiot" lights, to cut down on calls from customers who do not understand that properly working gauges move up & down. This scares your average driver.

So an EGT gauge is mandetory if you tow alot and want to reduce the potential for engine problems do to excess heat.
Your dad may not budge on the issue do to cost and his lack of confidence in the returned value.

Here is another option for you, make your dad a deal, you will buy & pay for out of your own pocket an EGT gauge and exhaust system and install them on the truck, and if you can show him an improvement with these mods over stock that he will let the company pay you back for the cost.
Now when you install these mods be smart about it, First install the EGT gauge only, then drive the truck for a week as you normally do and recored the EGT you are getting. Then install the exhaust system and drive it for a week again recording the EGT readings, you should then be able to show him a drop in EGT's and the cost benefit to the truck.

Remember, your dad is a bussiness man, if it does not make him or save him money he is not spending his hard earned dollars on it.

Good luck