I have a 2003 F-250 6.0L with a tuner Mod and I want to free up my exhaust system but I am not sure how far I can/should go. I have two friends who have "straight piped" their diesels with great results, but since their trucks are the other brands, (*shudders* 1 chevy and 1 dodge) I am not sure if I can or should proceed in the same fashion. Both of theses guys cut out their mufflers and converters last year and have not suffered any ill effects, rather, they both seem to have gained both power and mileage.(and their trucks sound GREAT!!) Should I follow suit? Is it safe? Is this even legal? Please help.

 

Hey man, I have an 2005 (made in Jan 06) F250 and she has a straight 5in pipe from the turbo out. I have had no problems and she runs great. Just check your state emission standards first to be sure you can.
Second, check your engine for an "Catalyst Emissions" sticker. If you do not have one, you can remove the cat.

 

It is safe to run turbo back systems with no cat and no muffler. The legal part you have to check with you local laws for that one. According to federal law it's not legal to remove a cat from any vehicle that requires one but the odds of getting caught are slim. If you still have any warranty left you will not find a dealer to work on one that has had a cat removed. From what i've read the only benefit to removing both are lower egt's and the turbo should spool faster. i have a cat back and system and do not plan on removing the cat until my warranty is gone. just my .02

 

The benefits that I have noticed are lower egt's and better sound when you romp on it. Actually the dealership here will only void your exhaust part of your warranty, now with the 6.4s your looking at a total warranty void but those exhaust are a completely different animal. Now state laws may be different, but Federal law mandates that you can't take the cat off unless you are going to work on it and put it back or replace it with a newer one. However, it does not stipulate that you can't work on a vehicle that does not have a cat(now if the garage is caught removing it without the intention of fixing or replacing with a newer then then they can shut your garage down), there was a thread awhile back as to way they don't want to work on a cat-less exhaust(although I never have had a problem with either warranty(although never had an exhaust claim either) or work done by the dealership) and I believe it was more mechanical in nature then legal. Now it might be state law(which there isn't one here in Tn, I'll have to check Tx though) that prevents the dealership from working on a cat-less system, but it's not federal.

 

Theres a newer Dodge diesel around here that is obviously running without muffler or cat., I think it sounds like crap.

 

Get a new downpipe, take the kitty to the vet and drop the muffler. On that '03 of yours it will sound INSANE with the jet whistle. Your friends will hate you, neighbors will probally move and you will LOVE the sound.

 

The ones that were before they went commonrail sounded the best(in my opinion).

 

do the '03's even have cats? i thought that they didn't.

 

03's will have a cat. 03's also are the loudest out of the bunch when straight piped. If you dont like turbo noise, keep the muffler and cat. If you want to be loud and sound like a 747, straight pipe it and never look back. I would go 4 inch from the turbo back.

if you do straight pipe it, be prepared for alot of questions from other diesel owners.

 

He is right, it does sound like a jet engine. Especially funny when I drop my son off at his school.

 

my brother has an '03 6.0 with an mbrp 4" turbo back exhaust with a muffler - no cat. i have an '07 6.0 with a magnaflow 4" turbo back exhaust with a muffler. 4" downtube on the magnaflow but similar systems. His truck does have a lot more turbo noise than mine. My recollection was that he didn't have a factory cat, i guess i was wrong.

 

I have acquired all of the necessary pipe....will be getting to cutting probably next weekend (not this coming), right after I get some more gas for the mig welder. Thanks for the input, I will repost when I get it done.

 

truck will run better with no cat, but it is a violation of the law so be careful