Looking to buy '06 2500. I was wondering when dodge started, or ever, put in the fuel saving option for the hemi'sin the trucks. When the 4 rearward cylinders shut down to save fuel. I'm not sure of the correct name, but if you could help me out that would be appreciated.

 

MDS. dodge started it in 2006 on the ram, however i know the megacab does not have it and i dont think the 2500 has it either, however i could be wrong about the 2500.

 

only 1500's have it. but not mega cab 1500's. only quad cab and regular cab 1500's.

 

Yeah, heard it's not on megacabs or 2500s. too heavy for it to activate maybe since the Mega and 2500 used the same frame.

 

The 2500's do not have MDS. From what I have been able to gather from 1500 MDS hemi owners, is highway gas mileage is a decent 19-21 mpg. City driving mpg hovers up and down within 14-17 range with the MDS.
For what it's worth, my 2500 gets a consistent 17mpg highway, 13-16 in the city.

 

and a lifted 1500 HEMI with 35" tires gets about 13-14 in the city and on the highway. Once I go over 60-65, my MDS will not kick in. Must be too much of a load on the engine at higher speeds for it to activate.

 

yep. thats what the dealer said. too much of a load for 4 cylinders. and yes, the 1500 MC is on a 2500 frame. but if you will be driving carefully, i might consider the MC. the mds is supposed to kick in cruising under 70. but like scott said (which i did mention to someone before), with a lift and a lot of extras which add much weight, it would not be effective to get a hemi with MDS. might as well get the MC and have the same mpg then.