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This will be some testing info I've tested personally over multiple trucks for those looking for that perfect sound. Really has zero effect on power but if you want that great cummins grumble we all know and love then think about this one>>>> so your in the market for an exhaust? There is tons of options and brands....so brand is pretty much irrelevant... only changes really are the outlet angle. MBRP comes back on a 45* outlet, Diamond eye 90* outlet and some others do 60*. Really it doesn't make that big of a difference other then the amount of sound you hear in the cab. Windows down 45* is quietest, 90* is loudest. You'll hear it crack and echo off everything. Windows up 90* is quiet at speed USUALLY, 45* can start to drone at speed due to the low pressure area behind the exhaust pipe/tip. It's not much but it exists. Larger the tip the more drone at high speed. So brand isn't a big deal. Now 4" VS 5", so there isn't a difference in power, we run 4" down pipes on second gens and the flow rate of 4" OD pipe is (3.8" roughly ID) is such a high CFM that it doesn't really matter on a 5.9 liter. Your Peterbuilt 13l CAT engine would like 5". So that said 5" is deeper, tighter fitting and tends to drone more in the cab. Yes it sounds better and I use 5" whenever possible. I love the deep grunt and burp sound, it just screams cummins! Cheap 4" systems will gain you the same power but it's a little more raspy. Now the MOST IMPORTANT part! The material!!!! This makes a huge difference in sound, no performance gains but the sound change is amazing. So alluminized tubing that 80% of us run is honestly crap...in salt conditions it corrodes in a way that turns it a black color over the years. The wall diameter is usually a hair thinner depending on manufacture. The pipe itself TYPICALLY isn't truely round, when it cools the seem in the tubing warps a little So assembly sometimes can be a bear. My personal pet-peeve...drone. Alluminized vibrates, bad...you hear it under the truck, you hear a sound reverberation in the exhaust note and worst of all it vibrates and resonates into the cab from the pipe vibration under the truck. I absolutely hate drone, it's annoying. That said, stainless steel is the best! Even with a thin wall tuning the vibration/reverberation and sound dampening of the stainless is second to none. Yes the tubing is vibrating still since it's connected to the engine and of course everything vibrates but, it flexes less and holds up better to conditions. No corrosion. Some surface rust may show since it's probably from china but it'll last much longer. From personal experience a stainless system also has a much more crisp and clean sound. A to B the drone is near gone in the cab even with 5" straight pipe and a large s300 or 400 turbo that's loud beyond loud. One reason stacked trucks sound the way they do is because the stack is stainless which cleans up the exhaust note. A 4" stainlesss exhaust vs 5" alluminized, the 4" sounds better and cleaner. Much more of the deep burp noise. My personal fav is the 5" stainless though, if you want to make people think you have a small pecker in your wanna be Peterbuilt this is what you use. Deep, crisp sound with little to no drone. Each truck is different, the amount of hangars and style hangar make a big difference as well. Stacks attached to the bed, vibrate the bed and cause droning well same with under carriage exhaust. Make sure your insolators are soft and properly sized. It'll help tremendously. ive personally had 7" stack systems that you couldn't hear in the cab with the windows up, a floating stack system looks a little weird when driving, it moves independent of the body floating on the insolators attached to the frame. But it's very quiet when you want it to be. This also reduces the stress on the pipe, turbo and manifold as the engine twists under load. from personal experience: I've got 2 2nd gens, one with 4" stainless straight pipe and one with 5" alluminized with a diamond eye stainless muffler (came with the truck brand new but I'm going to switch!) if you listen to both trucks in person the 4" stainless sounds much cleaner, crisper and more angry when your on the throttle. The 5" sounds like the echo in a tunnel. Like multiple vehicles are racing due to vibration and reverberation. Now for some word to the wise info...please for the love of god don't use the stupid crush clamps... they are crap. They bend the alloy pipe so bad it hardly ever comes apart without a torch. If you want to swap turbos or mufflers or whatever don't use crush clamps. I've had so many that are so bad I just cut pipe, butt it together and either band clamp it or weld it. It really sucks to do guys... if your gonna run stainless, good stainless pipe doesn't like to bend, so the crush clamps will actually bow and not compress the pipe but rather itself. it tends not to hold and a few miles later you got yourself an axle dump you didn't want it even an open down pipe and the muffler is in the grill of a Prius....don't use them. SO that said, the best, easiest and most adjustable/usable way is the overlap-band clamp. Slide your pipe seconds together, overlap the band clamp and get it really nice and tight. Some will have a pin hole leak right around the bolt location, if that's a problem you can use some paste on the pipes swelled overlap to help seal it for inspections and such. Now you can switch down pipes, mufflers, axle dumps etc without getting the hammer out. Just unbolt and slide apart! Stainless once again is the easiest for this and less opertunitly to leak. DO NOT use alloy band clamps. They are so weak you'll just break them! Regardless of what pipe you have to use get the stainless clamps. They hold up much better and longer. They keep there shape a little better also and seal/grab way better. If you don't have a swell overlap there is Butt-band clamps for 2 identical pipe sections to mate. Again stainless clamps are best. Little flexing means a tougher exhaust and better connection. Now that your up to date....spend the dang money and get a good exhaust, the $260 special online will work yes but sound isn't great, it doesn't last as long and though stainless is much heavier it's only about 20lbs. Unless your doing a full race build it's not gonna matter... you'll be happy you went for stainless in the end. Exhausts usually go on and stay, make sure your gonna be able to live with it for 5-20 years of ownership when the dodge body is gone and your riding the frame and engine cause it's all that left lol

Ok I love the sound of my truck, it’s straight piped to a large tip and has an open air box with great turbo sound. But I have to say it, it’s too loud. So simple question, can I make it quieter without sacrificing flow? Looking maybe at muffler or dual mufflers or maybe some sort of attenuator. I daily drive and use this for normal stuff like going through a drive through or stopping to talk for a second with friends or other parents at my kids school. But I also use it like a work truck, towing and hauling campers, equipment, firewood, etc. Can anyone help with this dilemma?

Hello, I would like to apologize for the long post! Okay so I'll start it off with what I have done to the truck so far. It is a 1998.5 2500 5-Speed 4x4 Cummins. A little under 900 maybe 1000 miles ago I have installed a new VP44, Airdog 100, OEM Cummins connector tubes, 7x.009 100hp injectors, and I also had to have my computer rebuilt because the throttle circuit was shorted out(I may also add that the truck used to prime for 3 seconds and it no longer does, I used to be able to access system function from a scanner and no longer can, The truck sounded ever so slightly different after I installed rebuilt ecm aswell). I have a few more things coming within the next 3 days including banjo washers for the bolt at the back of the head(I may also buy the Fuel Grommets at the return T soon aswell), BD Boost Fooler, and an Adjustable Turbo Elbow. There is also a programmer for sale that I may pick up aswell next week. But anyways now to my problem. I installed the new injection pump and airdog at the same time and then drove the truck for about 2 weeks and it sounded slightly different but ran fine.Then I decided to pull the trigger on some DFI 7x.009s . I installed them and the truck started up, smoke white for about 30-45 seconds and slowly went away and the "Air-Filled" idle started to go away too. The truck still had a rough idle after letting it sit for a while. So I got into contact with Chris and he sent another set out the next day. Boom the rough idle is gone. If I am in neutral and let the RPMs climb and then hold them at a certain spot the truck will shake quite a bit or whenever I accelerate hard the truck shakes quite a bit aswell. But the acceleration could be bad u-joint on front driveshaft maybe? If I give the truck more throttle there is an odd "miss" sound coming from the exhaust(not from the motor that I can hear anyways) The sound reminds me of an old non turbo 7.3. I ordered feeler guages and they will be here Monday and I will be adjusting my valves to see if that helps as they have never been adjust before. I know of two 2002 6-speed dodges that have 100hp and 150hp injectors and they do not sound like mine. Does anyone have an answer of how to fix it? I'm guessing maybe the tune in the computer is off and I just couldn't hear it with the smaller stock injectors or maybe the valves are opening slightly off and it is doing this or something?

My original plan was to change the front brake pads. I figured it would be a good idea to flush the brake fluid before removing the calipers, taking them apart and cleaning them and reinstalling them. I started in the back and right out of the gates I hit a road block. The bleeder valve on the rear cylinder was rusted tight and it sheared off when I tried force it. Guess what? The other side was the same way. I replaced them both and in the process I sprung a leak in the middle of a brake line. I replaced the brake line and FINALLY got moving with things. I flushed the system fairly well and found a lot of sludge inside both calipers. They did clean up nice and there was no noticeable scars or damage to anything. The seal kit that I bought was the wrong kit. My calipers don't have the two separate pistons, it is just one large piston. It was late and I wasn't about to make a fourth parts run. The seals did look good and I cleaned them up the best I could. I would have much preferred to replace them. I put everything together and it drove 100% better. The shimmy was gone and I was home free. A couple of days ago the shimmy started to come back, slowly, as I applied brakes. Today, after I flushed the power steering I took it for a spin around the block and the shimmy was getting me worried and pissed off. I can feel the steering wheel shake and there is a pulsing feel--only when I am pushing on the brakes. I parked in my drive way and I could smell brake. I stuck my head in the wheel well and the driver’s side was hot, the passenger’s side smelled/felt fine. I would bet the farm that the caliper is sticking because after I put it back together last week the braking was smooth. There isn't too much to a caliper and I don't want to buy a new one, however, could this be caused due to bad seals? It is easy enough to remove and take apart but would I be better off just replacing the entire caliper? Oh yeah, exhaust. As I was under my truck farting around with brake lines last week I noticed that my tail pipe, right where it comes out of the muffler had completely rusted through and that last section is dangling on the hangers. I was hoping that there would be enough metal to clamp or weld to rejoin the two sections, but there isn't. I am sure I could replace the muffler and piece in a coupler for a fix, or would it be better and more cost effective to just install a new exhaust from the turbo to the back bumper. Any product I should consider?

Well guys I'm needing a bit of advice. Looking to knock the drone out of the cab of my truck while keeping the sound from the tailpipe. So which FTE resonator should I use 17 inch or 30 inch? I have a MagnaFlow SS 4 inch flow through muffler I just want to knock the drone out.

Hi, I have a 97 4x4 club cab, 5 speed. I found a "cat back" 4" exhaust on Craigslist for $50.00. I'm trying to determine if the stock downpipe is worth the cost to replace (seems it's about 75-125) also. I believe it's 3.5" from the turbo down to the bend under the passenger seat (correct?). The truck is stock (and will stay stock) except for BHAF. I'm looking to make the motor exhale better, but not sure that the difference in the downpipe will be worth the cost. I occasionally haul a trailer (4.5 to 9 k) but the motor never gets hot, nor do I push it. What do you think? I'm also making the "cat " either go away or be just a hollow shell. I would appreciate input please....Thanks,paul