Hemi Gas Mileage

[Delano1981]

Hello Everyone,

I bought a used 2007 Ram 1500 QC 4X4 with the Hemi engine about 2 months ago. I have been trying to recover form the shock of the gas mileage ever since. Right now I am getting 8 mpg city driving. But, it is mostly to and from work which is 1 mile each way. It seems to me it should do better than that. I have replaced the sparks plugs with stock plugs, cleaned the PVC valve, replaced the EGR, and put in a K&N filter. Truck has 129,000 miles. It appears to have an aftermarket muffler. When it goes into MDS mode I can really hear it and it ticks noticeably when in MDS. I still need to do some highway testing for mpg. I met a guy who has a 2006 truck just like mine and he says he gets 12-13 mpg city. What do all of you think? Is it because of the short distance to work and back that causes the bad mpg?

Thanks

 

[Dubstep Shep]

Uhhhhhh the 2007 doesn't have MDS.

 

[98hemi-ram]

Uhhhhhh the 2007 doesn't have MDS.

Incorrect. Dodge started putting MDS in the Rams in 2006. I know because I had an 06 and used my programmer to turn it off since I hated the god awful drone the exhaust got when it kicked in.

To the OP your short drive definitely isn't helping your mileage. I drove about 2-3 miles to work with my old truck and was burning way more fuel than either my dad or grandpa did with there 07 Rams. My mileage did get better on the highway but still never got as good as they got with there trucks.

 

[Delano1981]

Uhhhhhh the 2007 doesn't have MDS.

I am sure it does. I printed the equipment list from Dodge based on the VIN # and it does state that the engine is equipped with MDS.

Here is a link to a car buying guide mentioning the MDS Hemi engine:

PickupTruck.Com: 2007 Buyers Guide - Dodge Ram 1500

Thanks

 

[Delano1981]

Incorrect. Dodge started putting MDS in the Rams in 2006. I know because I had an 06 and used my programmer to turn it off since I hated the god awful drone the exhaust got when it kicked in.

To the OP your short drive definitely isn't helping your mileage. I drove about 2-3 miles to work with my old truck and was burning way more fuel than either my dad or grandpa did with there 07 Rams. My mileage did get better on the highway but still never got as good as they got with there trucks.

Thanks for the reply. What do you think of the noise when MDS kicks in? I also have the droning exhaust, but also it is noisy and ticks noticeably when it activates.

Thanks

 

[Dubstep Shep]

Welp, news to me. I didn't think they started doing MDS until they redid the hemis.

 

[justin13703]

If you're only going 1 mile each way then your mileage will look bad. On such a short trip you are spending most of your time accelerating and there are way too many variables when it comes to city driving to compare to someone else's truck unless he drives the same exact path as you every day. Put it on the highway for a while and see what it does there. Don't forget to reset you mileage reading when you do.

As far as the MDS noise, it does sound a little different when it is activated. If you have an aftermarket exhaust it will be extremely noticeable because it will essentially sound like a 4 cylinder car with exhaust. The only ways to deal with that are to go back to a stock exhaust system, or turn MDS off with a tuner. Putting the truck in tow/haul mode will also deactivate the MDS.

 

[HemiLonestar]

Welp, news to me. I didn't think they started doing MDS until they redid the hemis.

VVT started with the redesign. The blocks were always designed to have it, even back in 2003. The car version got it back in 2005, they just decided to do it to the 1500's for a sales gimmick and to show they were committed to mpg's...

"hemi gas mileage" is a contradiction in terms...

 

[Delano1981]

Thanks for the replies. I did a highway test today on the interstate, hilly terrain at around 70 mph. On a 30 mile trip I got 18 mpg, which is exactly what the manufacturer spec is for highway mpg, so it appears everything is Ok as far as mpg.

 

[Weezer]

I was averaging 14 to 15 but with the lift and Toyo MT's I'm at 12 to 13 mpg but I didn't get a truck for good gas mileage

 

[OutLore]

I was averaging 14 to 15 but with the lift and Toyo MT's I'm at 12 to 13 mpg but I didn't get a truck for good gas mileage

Exactly. When people question my gas mileage, I tell them, then ask them what their tow rating is.

 

[YeahItsGotAHemi]

I have an 07 with MDS. I have a K&N CAI and a Flowmaster 40. I average about 14.5 on highway and 13.7 city. Highest I ever saw was 15.6.

 

[Grown in Tx.]

I can get 22avg on my weekly driving which is half city and highway. That is driving like I'm low on gas, last week i played a lot and it was 15. That's in a 2014 single cab with stock tires. Just normal driving gets me 19mpg

 

[R.L.K.]

@ the OP :
If your truck has 129k and has never had an oil catch can your intake plenum is likely loaded with gunk and carbon buildup from the " Normal " dumping of oil into your hot intake through the PCV discharge / Venting system . This causes issues of many sorts down the road .
Go to www.oilcatchcan.com for some interesting reading on the PVC system .
This will help , it won't give you a giant increase in mpg , but it helps and is just a good idea .
There are many flavors of Oil Catch Cans out there , I went with the Elite Engineering one mainly due to an improved head design .

Pic of mine mounted .




@ 5,200 miles during an oil change .
8.5 OZ of oil that did not make its way to my intake !



Hope this helps !

 

[preachp]

Hi delano,
I would look at the exhaust for a leak with the ticking noise and do a visual of your rocker arms, especially number 5. And yes mpg is due to short runs. These engines drink fuel when they are cold and make it up once they are warm and have run for a bit.
I'm not saying there is an issue but if your hearing the noise enough to discern it, it should be checked for peace of mind.
Enjoy the truck and have a great day,

preachp

 

[Weezer]

How can you tell when MDS kicks in? I have a Magnaflow exhaust and I never can tell the difference or is it that I don't have MDS

Sent from my LG-D851 using Tapatalk

 

[BgHrn]

Yep, my 06' has MDS, but I turned it off. Even with bolt-ons, leveled and 35's, I still get 16-17.5 mpg on highway. But in the winter, it drops to 14-15.

 

[HemiLonestar]

How can you tell when MDS kicks in? I have a Magnaflow exhaust and I never can tell the difference or is it that I don't have MDS

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Usually the exhaust gets a flat note to it. Your 08 was built with it (all 1500's after 06 were). Only way it wouldn't function is if it was tuned off with a tuner.