Planning a 16+ hour drive to northern Michigan at the end of the month. This will be my first long trip in the R/T, and with gas prices what they are, I want to get the best mpg possible for this trip. Was wondering how the A/C system effects the MDS? A/C units in cars with smaller engines seem to put a strain on the system and lower mpg, so I am wondering if running the A/C will lessen the amount of time my R/T will kick in the MDS, or if the engine is powerful enough to not notice the A/C?

=M=

 

Since the AC compressor takes usable horsepower to run, it can't help but affect MDS, but I doubt you'll notice it much, if at all. I leave my climate control in auto (at 70 degrees) and have still been averaging 28.4 mpg.

 

i wish i could average that much in my magnum.. highway i think the most i've seen was 23 with the hemi and about 13 in teh city lol

 

I have never noticed the compressor kick in while the A/C is on. I don't feel any difference. With or without I still get about 21, 22 on the highway regardless.