My new Dodge RAM CTD from the factory came with a 4" exhaust. I installed the monster exhaust from turbo to tip. It is not worth the money. If you have a new RAM CTD your best bet is to utilize your factory pipes and just add a straight thru aftermarket muffler. You'll save yourself a bundle.

 

yep... ditch the cat, and high flow muff and you'll be set. or go bigger than 4"

 

edit: I fixed the title of your post for you

 

Yes it is true you don't a new exhaust if you have the 04.5 with the 4" turbo to tail exhaust. However those of us that own the older modles will benefit from a true 4" exhaust all the way back.

As far going to a 5" exhaust the gain does NOT even come close to making up for the cost, even if you keep the truck for 20 years

 

It depends on what you're doing. The common rail trucks definitely benefit from 5" exhaust before the 2nd Gen VP44 equipped trucks do. With the TST box on level 5, I recorded a 150F drop in EGTs with the addition of a 5" exhaust system on my 03. A 4" exhaust system on that same 03 only recorded a drop of 75F.

Rod

 

my 5" system cost me $329. how much does a Banks 4" system cost?

and I figured once the HT3B went on, I wouldn't want to neck down to a 4" pipe from that 5" outlet!

Forrest

 

I really like my 4" Bank's DP...don't think I got ripped at all. Everyone makes different products geared for different people. Quit ripping Banks. They make a product that is not the most bang for the buck, but has the best fit and finish of any product, has been kinda fool proofed for dum dum's that can't watch their own gauges, and just generally cater to the towing crowd. It is a free world...buy what you want. If you bought something not knowing what you are getting, it is your fault for not knowing!

Banks makes the only 4" true downpipe that I know of and the price was reasonable. I did not need the rest of the "shiny bling bling" system because I wanted to make my own budget system. I was able to do this because I can weld cut grind etc. Not all can!

 

I made my own 4" HX40 downpipe because I can weld cut grind etc.

 

Rod -- thats cool! an additional 75 degrees from 5" over 4" on the TST box. what were the other conditions?

TST box on 5/5, right?
what turbo?
what intake system?
what driving conditions?

 

I went with the 5" because it produces a much deeper tone straight piped.

 

Ack, sorry, I should have given those. I was actually on 5/4, with a KSB1-2, Ram Air III, unloaded, and pedal to the mat for 10 miles.

Rod

 

Ahhh..only in Saskabush! Pedal to the mat for ten miles! Rod, I've been stuck on Vancouver Island for the last 6 weeks, and I can't find a stretch of over a mile to let her rip! O Well, soon I'll be back there, shovelling snow,swatting 'skeeters and using cruise control again!(all in the same day,Lol!)