I just purchased an 06 Ram with the Hemi. Yesterday i installed a 50 series flowmaster and a 77 series K&N intake. took it for a test drive and everything was fine.
However, This morning on the way to work i noticed something strange. When i hit a cruising speed, after a couple seconds my exhaust sound changes.
It starts sounding the same way my old 5 speed manual would sound if i slowed down and then tried to accelerate without downshifting.
If i let off the gas, and then go back the sound stays, but if i slightly accelerate...it goes away until i start cruising again. It does it at all speeds!!
Is this the MDS kicking in?????

I'm hoping it goes away, cuz its very annoying!!!!

 

Likely is as its the cutting out of cylders. exhaust sound will change as its running on less cylders .

 

I would agree. Since those cylinders aren't firing anymore, your exhaust note will change. You didn't notice it as much with the stock exhaust, as it's quiet. But a flowmaster would make something like that VERY noticeable.

 

Yup, sounds like the mds dropping cylinders.

 

Thats what it is, and thats one reason why I like the 03-05 Hemis better.

 

Figures I love the sound of my exhaust until the mds kicks in, but i'm not sure if i'll keep the exhaust now. Not to sure how it sounds outside, but it sounds terrible in the cab!!!!

 

The '06 Heavy Duty Rams don't have MDS... only the 1500's

 

There was an interesting article about the new Hemi's a couple of months before they hit the showrooms in 4 Wheeler magazine. The problem they had with MDS was what you are describing, after the cylinders dropped, they were not happy with the exhaust note. The engineers had to design an exhaust system that would resonate the sound of a V8 even with only 4 cylinders firing. The article also went into detail of exactly how MDS works. It was pretty interesting and might be worth trying to google. I would love to have an 06 Hemi and I hope you enjoy yours.

 

thanks lowcountry...i'll look into it!

 

corsa makes an exhaust especially for the 06 hemis. kind of expensive. supposed to sound beautiful but i dont know. i have the forty series on mine and it sound great until it drops the cylinders around 20-25 mph and 60-65 mph. i just learned how to drive around it for now until somethin else cheaper than the corsa is developed