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Disabling the MDS.

18K views 27 replies 10 participants last post by  jonsnow 
#1 ·
I installed the Superchips Cortex 91 octane performance tune, and today I turned off the MDS on my 07' Ram. I am hoping my fuel economy doesn't drop after this change. I did notice I do not have to push very much on the accelerator to increase speed, and my truck seems to hold speed much better. If you have done this mod on your truck, what have you experienced? Did you like it, or re-activated it for any reason?
 
#2 ·
I deactivated it with my superchips because I hated the way it sounded with the glasspack. Besides, if I wanted to run 4 cylinders I would've purchased a Honda.
 
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#6 ·
It really does help a lot it activates every time you steady cruise and every time you decel so 5 is a very likely thing from stock. I bet to you were on it a little more than you might think since it moves better with all 8 cylinders lol.
 
#8 ·
When did MDS start being used? I read somewhere that it started with 2006 models but I'm pretty sure my '06 doesn't have it....it might be because I have a 2500, was it only used in 1500 models?
 
#11 ·
Cool, I've been wondering about that. Thanks! I do know the new 6.4 hemi uses mds in 2500 and 3500 trucks.
 
#13 ·
That's strange John. I had mds on in my truck for a while before getting the tuner and I don't recall having that substantial, if much of any, loss in mileage. Maybe I just drive funny
 
#14 ·
Ya, I don't understand that much difference. I don't use the on board MPG calculator. I use the old standby calculator to figure MPG's. I may have a trip coming up to east Texas and I may deactivate MDS and see what I get running 75MPH. Then I will run home, same speed, with the MDS activated, to see what the difference is on my truck.
 
#17 ·
Now you got me thinking about turning it back on to see if it goes up. The main reason I cut it off was because it sounded like a school bus with the cherrybomb lol
 
#19 ·
Maybe that's why I didn't notice a loss. Very hilly here as well.
 
#20 ·
I bought my 07 brand new and I was getting 16.6 hand calculated MPG stock. After headers, gutted cats and custom exhaust I was getting about 15.9 and this was only 2 months after I bought the truck. I threw a code because of the gutted cats so MDS deactivated. Even after 4.56 gears I was still getting 14.9 mpg still with no MDS. I really can't see MDS being more than maybe 1mpg if you really babied it all the time.

Look at the 05 hemis. They don't really get any worse mileage than the mds trucks do
 
#21 ·
I bought my 07 brand new and I was getting 16.6 hand calculated MPG stock. After headers, gutted cats and custom exhaust I was getting about 15.9 and this was only 2 months after I bought the truck. I threw a code because of the gutted cats so MDS deactivated. Even after 4.56 gears I was still getting 14.9 mpg still with no MDS. I really can't see MDS being more than maybe 1mpg if you really babied it all the time.

Look at the 05 hemis. They don't really get any worse mileage than the mds trucks do
:thumb:

HemiFun05 :dance:

:D
 
#23 ·
These trucks actually get pretty good mileage considering what theyre capable of. I was running 14.81 Ets on a 100% stock truck at 4850lbs on stock tires and getting 16+ MPG. Can't really complain
 
#25 ·
Hi All,

I get routinely 19 mpg highway and 15 around town secondary roads. That is with a 5600 lb 4X4 truck. Plus this thing can pull, drag, and haul pretty much anything it wants to, up to about 4 tons of course. I think these are awesome trucks. That kind of mileage and 395 hp with 410 ft lb of torque is phenomenal! Haven't tuned and probably wont for a while it is good for what I use it for the way it is right now.

preachp
 
#27 ·
Hi jonsnow,

In 2013 there was ALOT of "tweaks" to the RAM 1500. As a matter of fact there were so many that it became a somewhat different truck. The 3.55 gearing and that hemi give this thing some serious grunt, especially when it is in 4LO. It has so much grunt it makes the brake moan because it wants to GO! I can't say one bad thing about this truck and I have had it since December and I put 6000 miles on it, and it still just makes me go wow when I ask it to work.
All I can say is I have never had a vehicle that repesents and has the abilities of this thing.
BTW that mileage has been consistent and I am not always nice with the go pedal.

preachp
 
#28 ·
I put a manual power tune with MDS shut off on my 09 hemi. I. Checked my mileage on a 600 mile road trip this weekend. My mileage jumped on average 1.75 mpg. Pretty happy with that.
I also shut off the speed limiter and raised the rev limiter a little( not sure what the safe high limit is). Guess I need to try the economy tune next and see if I gain any mpg. I
 
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