Hi everyone,<br><br>I got to thinking the other day, after watching several Durapacs go by, whether it would be worth adding a truck muffler to our exhaust systems, to reduce the noise.<br><br>I expect I will get a lot of flack for this, but wonder anyway. Has anyone added a muffler to their stock exhaust system? If so, what happened? Did the noise diminish? Did the overhaul engine performance suffer very much?<br><br>There are quite a few members who run stock trucks and are happy with the performance, but maybe not so with the noisy exhaust. Is all the noise we hear from the exhaust? Does some of this noise come from the engine itself? What are the differences between the 03 engine and the 02 (and earlier) which make the 03 engine so quiet.<br><br>Thanks for your patience, all arguments valid.<br><br>Thx<br><br>Mariner<br>

Big difference is pilot injection on the 03. It gives three pulses of fuel per power stroke. First pulse 10% of fuel starts the burning, second pulse, 80% of fuel main burn, third pulse, 10% of fuel finishes and cleans up the main burn. In addition the skirt, sides of the engine block are extended lower.<br><br>The 02 models and before had a single pulse for power stroke.<br><br>Different fuel pumps, different turbocharger The 03s have a much larger exhaust, 4 inch all the way back.

Actually the exhaust on the 03 is 3.5&quot; turbo to muffler and 4&quot; muffler back.

.....Is all the noise we hear from the exhaust? Does some of this noise come from the engine itself? What are the differences between the 03 engine and the 02 (and earlier) which make the 03 engine so quiet.............


Much of the noise comes from the oil pan area. Other areas are the exhaust manifold, the exhaust elbow and down pipe. Blankets are available from is available from Advanced Thermal Products, including a beautiful (but expensive) hood blanket. I don't believe the exhaust is any louder than a gas engine. Have looked at the underside of your '02 yet? There is a resonator and muffler already there.

commatoze does these oil pan covers really work or it is money spent for nothing<br><br>they also carry a valve cover blanket i didnt know that much noise came from the valve cover<br><br>does anybody have these parts or know anyone who has used them with results<br><br>very high $$$$$$$$$

I don't have first hand experience with the products, only what I read from users. They all say it worked fantastic and were very pleased with the results.

Hi,<br><br>will just replacing the muffler help eith temps and flow from stock vs. going for the whole exhaust?<br>Which muffler is better.<br><br>Thanks,<br>Bill

I installed a 4&quot; system on my 3500 , didn`t like noise while pulling my 5th wheel so i installed another 4&quot; muffler it silenced it perfect ;D ;D ;D

Straight pipe it and add the Scotty II hole, the engine noise will be gone ;D

I see you have an '02. Do you have the hood insulation? Lots of noise comes from the hood and DC cut some '02 goodies like the insulation. More noise comes from the oil pan too. Start the truck and get under it. Can hardly think its so loud. Also I would say that adding a muffler to the stock system would be very bad for EGT's.

I added an extra muffler to my 4&quot; Jardine system and it did a good job of quieting the exhaust down. It's quieter than stock now. Still have a drone type noise which is the stock air box with the snorkel removed.