Trans downshifting automatically - normal??
Veteran
Joined: May 2009
Posts: 482
Likes: 1
From: Texas
i coast a little over a mile every morning to a long stop light off the hwy. if i coast all the way, i get to the red light doing about 20mph.
3.55 what's everybody got that downshifts?
Last edited by jawsdc; May 19, 2010 at 03:37 PM.
Professional
Joined: May 2010
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From: Vidor,Tx
<-----3.55
Rookie
Joined: May 2009
Posts: 65
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From: Michigan's U.P.
I don't use tow/haul mode, but I've had the same experience w/ the cruise on going down a hill. I agree it's to keep the truck at the speed set by the cruise.
Veteran
Joined: Jun 2010
Posts: 255
Likes: 1
From: Northern California
I have a new (see signature) with only 800 miles on it. In drive, when I let off the gas, say from 65 mph, as it is slowing down, it will downshift on its own (you can feel it and see rpms jump a little) a couple of times. I just sold an 04 F-150 with the 5.3L eng and when I let off the gas in that thing, it would coast forever, never downshifting on it's own. It's not a complaint, just wondering if this is normal, never having had a Dodge before. (Actually it will save me some brake pads over the long term, hopefully not at the expense of the trans.)
Every vehicle I have ever owned, be it Dodge, Ford or Chevy would, when coasting and "slowing" down, downshift. From my '66 LTD 3 speed to my '09 Ram. The slower you go, the trans will hunt for the appropriate gear for that speed.
Who wants to be coasting and slowing past 40 mph and be in D5, step on the gas and have the drive train hesitate while it finds the right gear.
Also, it seems you may feel more slowing because with 800 miles everything is still tight in you truck. After 3 to 4k miles my truck settled about 150 to 200 rpm lower when cruising at 65 mph and actually seemed to coast farther.
Agreed that when in cruise it will downshift going downhill to try to maintain your speed.
Champion
Joined: Dec 2007
Posts: 3,563
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From: Ontario, Canada
That is supposed to be seamless as it is in my truck, I would challenge anyone to tell me with their eyes closed to tell me when mine goes into MDS. I didn't think mine worked is why I pressured so much as to email Dodge and well finally they came up with the light on the early builds but no mater light or not the only thing I feel is the trans downshift if you coast from 60 to a stop it will downshift when it needs the right gear but not right away as soon as the gas is off, it coasts and remains almost at lets say 60 mph for a few seconds before slowly decellerating and then it downshifts when the speed get slower but it is not like as if you downshifted to 3 third while going 80 mph it is just a little shift. Nothing really noticeable I suggest you take yours in.
Veteran
Joined: Feb 2010
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From: beavercreek, OH
my 09 coasts forever, i read in the manual correct me if i'm wrong that our trucks if coasting shuts off fuel to conserve. with my exhaust i can hear and feel the change in MDS mode, it doesn't down shift
Veteran
Joined: Jun 2010
Posts: 255
Likes: 1
From: Northern California
This is interesting.
Don't know much about the mechanics of the fuel shutoff when coasting, but if it does cut fuel to the engine and shuts it down, I would think you would slow down faster than if it didn't cut fuel.
With the engine "idling" in coast it would be overcoming most of the friction of the drive train and engine itself and let you coast farther. If the fuel is cut off the engine is not running hence nothing to counter the friction of the drive train, coast less.
In days of old if my engine stalled (fuel cut off) at speed and in gear it was very noticeable, very different than coasting with the engine on, slowed down real fast.
Maybe with the shutoff, engine rpm drops and it feels like a downshift.
Regardless, as the vehicle gets slower the transmission will downshift as the speed gets lower, it is designed and programed to do that.
Don't know much about the mechanics of the fuel shutoff when coasting, but if it does cut fuel to the engine and shuts it down, I would think you would slow down faster than if it didn't cut fuel.
With the engine "idling" in coast it would be overcoming most of the friction of the drive train and engine itself and let you coast farther. If the fuel is cut off the engine is not running hence nothing to counter the friction of the drive train, coast less.
In days of old if my engine stalled (fuel cut off) at speed and in gear it was very noticeable, very different than coasting with the engine on, slowed down real fast.
Maybe with the shutoff, engine rpm drops and it feels like a downshift.
Regardless, as the vehicle gets slower the transmission will downshift as the speed gets lower, it is designed and programed to do that.