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livefortheday2308 04-08-2010 06:06 PM

2005 HEMI MDS Issues
I have a 2005 WK with the 5.7L HEMI MDS engine in it. I was used to getting about 14 mpg around the city and then when the MDS kicked in on the highway (or above 55 mph) I would see it jump sometimes up to 23 mpg. My last oil change or so that highway number has dropped off to about 18.5 mpg and the whine from the MDS system has not been as loud. I have only been using 5w-20, but it seemed like the drop off happened after the oil change when I used Royal Purple, I have since switched back to Mobil 1 on my last oil change, but the highway mpg's have not gone back up. I was wondering if anyone had an idea of what it might be or if you have had the same issue and what you did. Any help?

blackpepper 04-08-2010 06:09 PM

Re: 2005 HEMI MDS Issues
How many miles do you have? Start simple with some fuel injector cleaner.. if you don't notice an improvement after a tank and if your miles are high, you might want to think about diff fluids.. tranny fluids or new spark plugs.

livefortheday2308 04-08-2010 06:51 PM

Re: 2005 HEMI MDS Issues
Thanks, I just past 41,000 miles, have you found any fuel injector cleaners that have worked better than others for you (if have used any)?

Joe in PA 04-08-2010 07:04 PM

Re: 2005 HEMI MDS Issues
BG, Lucas and seaform work for me. I usually just buy whichever one happens to be on sale. :D

blackpepper 04-08-2010 08:36 PM

Re: 2005 HEMI MDS Issues
Ditto.. or I just get them at the gas station before I fuel up.

cain45 04-10-2010 07:54 PM

Re: 2005 HEMI MDS Issues
BG 44k all the way!

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