Hi Guys,

Yes..I am the latest green horn on the site.

I just purchased a 2007 Ram 1500 SLT with 39,000 miles (from a dealer 2 hours away). The truck is a 9 out of 10 as far as condition goes. It has a transferable bumper to bumper warranty for 7 years etc and an 80 point check from the dealer (for whatever that's worth). The only modification the truck has is the dual Magnaflow exhaust which sounds great.

My question is: The truck at very light throttle sounds like it's misfiring / running rough. This is when I am maintaining a steady RPM and speed (not speeding up or slowing down. It's like when the engine finds the speed / RPM that it's going to sit at, it sounds like it's spuddering or slightly misfiring. It also seems to stumble a little when accelerating from that steady speed or rpm. It does it from around 1300 rpm to 2000 rpm and mostly in overdrive / 5th gear. It runs great at when you put your foot in to it.

Has anyone else experienced this? I got the proverbial pat on the head when I took it to my local Dodge dealer (after the road test with the service manager). He said "you need to change the plugs if they haven't been changed and the throttle body should be cleaned, you have no check engine light...your Magnaflow exhaust is making sounds you wouldn't normally hear with the stock exhaust".

Is this service guy out to lunch, would the plugs be toast at 39,000 miles? Has anyone had any experience with this issue? Any help would be appreciated!?

Thanks!
Matt

 

I hate to be the one to respond to my post but....is this really what's going on???.......

Flutter sound after catback install..This is cause by removing the gigantic muffler and/or resonators that suppressed the pulsating effect caused by the 4cylinder(MDS) activation. Since all 8 cylinders aren't firing, there are only have the exhaust pulses flowing through the exhaust. That is why you hear what you do. very annoying if you have not experienced this. Best i can describe the sound is as if there is a helicopter submersed in water directly beneath you.

 

Plugs on the hemi need to go every 30k. You could pull one out to check the gap and see if it was done before you bought it.

Sounds like the MDS could be causing that effect. I think there is a way to deactivate it without a scanner? I have an '05 so none of that to worry about. If you turned it off temporarily you could at least see if that fixes the problem.

 

The book does say 30K for the plugs, but I'm pretty sure they'll go longer. I changed the plugs in my C @ 49K. The gaps were in the .0050 range. The "stumble" could be a result of a dirty TB. They're easy to clean. A Sea Foam treatment might be worthwhile.

 

Thank you for the replies.

It would be interesting to be able to listen to it MDS disengaged (if you can)?

I heard that Sea Foam is pretty good stuff. How do you go about doing that?

I have to say that I am more than impressed with the power of this truck. I use to own an 06 Corvette, so it's not my first V8 with lots of power by any means!

Thanks!

 

Push the tow/haul button on the end of the shifter and drive it. This will lock out 5th gear and MDS. If the issue goes away, then it is just the MDS and no worries.

You can get a tuner like a Diablosport Predator or Superchips and disable the MDS if you want to.

 

It looks like it's the MDS. It runs great on tow haul / OD. The Magnaflow exhaust with 4 cylinders running really sounds strange. It goes against my better judgement....but I guess that's what a V-4 sounds like?

Thanks for the replies!

Is there any must do mods to help with the longevity of the truck.

Thanks!

 

Get a tuner and disable the MDS. Your ears and torque converter solenoid will thank you

When the MDS kicks in, the lock-up clutch releases 30% which is why the rpm's go up about 300rpm. This can"t be good on the clutch over time I wouldn't think.

I just removed my Magnaflow cat-back and reinstalled the stock stuff trying to pinpoint a bearing noise. I run the 93 octane tune and have turned my MDS back on trying to see how high I can get my MPG. I have a lifetime powertrain warranty so I'm not worried about the solenoid. It's covered
I'm kinda liking it quiet since I drive 72 miles round trip to work everyday. I have a Mustang if I want to make noise, but I am not going to sell the kit. I'm sure I'll get bored and put it back on later

 

haha you guys just solved my problems too this site is awesome! i put a mbrp exhaust on my 07 once the mds kicks in it sounds like a friggen subaru

 

That's one reason why I'm changing the lifters out when I get a Charger! V8 Hemi needs to sound like a V8 Hemi, my daily driver is an 04 Ram with a non mds hemi, so the same engine in a vehicle 1500lbs lighter and less aero drag I can definitely afford gas for!. Plus I've heard about lots of timing chain failures on MDS vehicles...no thanx!.


On the flip side, I'm glad your truck is ok and the mds was what was causing the weird noise, I heard it for the first time on my cousins 2013 truck and was like wtf, but remembered it had MDS.