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I have the '06 HEMI with MDS. But, they didn't come out with "MDS on" indicators until later years. My question for those "later year" folks is this: When your MDS comes on, do your RPMS drop, stay the same, or go up?

The reason I ask is because my personal cruising speed is roughly 67.23mph - and I set it just after the RPMs drop from ~2100 to ~1800-1900. I'm wondering if I'm just dropping to a lower gear, or if that is an MDS RPM drop.

Logically, it seems that with MDS on the RPMS should be greater or equal than when its off. But, what the heck do I know?
 

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...with "MDS on" indicators until later years.
There's a light...? Not in my '07. I'll have to check my build date. I wonder when they started putting that in. It would be pretty neat to see when the system is activated.

I've tried some conservative driving to take advantage of MDS. I can't say I ever noticed a change in RPMs, though. I'll have to start paying more carefull attention to check.
 

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There's a light...? Not in my '07. I'll have to check my build date. I wonder when they started putting that in.
I think they put the MDS on indicator starting with the 2008 MY.
 

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I don't think the MDS drops the RPM,, RPM only changes when gears change.

I think the last drop in RPM which made you think its due to MDS is the overdrive gear.
 

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Discussion Starter #7
I don't think the MDS drops the RPM,, RPM only changes when gears change.

I think the last drop in RPM which made you think its due to MDS is the overdrive gear.
I think you might be right, the question is which is better? The very last notch of that overdrive or the MDS? I have trouble telling and there is little to no flat ground here to try test runs with.
 

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My '09 EVIC doesn't display MPH or "Fuel Saver Mode". Is mine broken?

I know that my wife's 300C has this feature, although the MPH always stays at 0.
 

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There is no rpm change as Ahmed noted. And he is correct as either the 5th gear or the lockup torque converter engagement is why the rpm drop is noted.
Our Commanders do not have a mds display that I'm aware of.
If it is working correctly, the shift to mds should be transparent.

BTW,.....Roughly 67.23??? Good grief, you have a very precise interpetation of roughly.

LOL,
Rob
 

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Discussion Starter #10
BTW,.....Roughly 67.23??? Good grief, you have a very precise interpetation of roughly.
Roughly - give or take a hundredth.
 

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On my 2006, loaded Jeep, what I've noticed is:

At about 60 MPH with MDS off, I run at 1,800 RPM. (8 cylinders)
At about 60 MPH with MDS on, I run at 2,000 RPM. (4 cylinders)

That 60 MPH, seems to be a normal point for me. Depending on tire pressure, road conditions, wind speed/direction, drafting, etc.

With a decent tailwind, I've been on MDS past 67 MPH. On the other side, there are times I can't keep it above 57.

And forget about keeping it with cruise control on.

Tom
 

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Roughly - give or take a hundredth.
I like to cruise between 65.667 and 65.668 most of the time. But sometimes I'll cruise at 65.669
 

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Great thread, I was looking for some mods I could make and this one seems top drawer ... low cost and could actualy save some gas/cash too!

If everything goes as planned I should pick up my Commander tomorow some time *finger crossed* , I already have an appointment to get a new front shock/strut replaced under warentee.

First mod will be to remove the wind dam underneath so snow does not rip it off, then wire up a MDS LED over the holidays.
 
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