Hello
 

Kool site , have a Question, how can you tell a 5.7 from a 5.7 MDS

Tough to tell externally, but probably the easiest way to tell is to find the electrical harness that connects the oil circuit solenoids.

eyes what up my name is kyle im the proud owner of an o6 hemi ram

all 5.7s in lxs have mds. i know the first ones in the trucks didnt. not sure about later on.

when ur driving, you can hear it drop to 4 cylinder mode. just looking at it, it is probably difficult to tell without pulling the valve covers off. if the oil cap is there, MDS engines require 5/20 oil and it should say it on the oil cap.