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  #1  
Old 11-08-2013, 12:26 AM
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2014 Overland 3.6 weird downshift

4,000 miles. Has most recent transmission flash. Everything fine with shifting for last 500+ miles.

Wife and I decided to drive to Reno from Colfax, CA to visit Scheel's outdoor store and have dinner. Long about Emigrant Gap on a long downhill in Eco mode, at about 70 mph, the transmission apparently downshifted and the RPM went to 4,000 ( I later experimented and concluded that 4K RPM was consistent with 4th gear). I think I was in Cruise control, but I tapped the brake in case the cruise has decided to gear down (going downhill)

RPM immediately settled down in keeping with road speed and 8th gear in Drive and we continued on to Reno. Thought I might have inadvertently tapped the DS paddle, but doubt that I would have tapped it 4 times without knowing it.

On the return trip, we were once again on a long downhill near Emigrant gap and this time, I knew that cruise control was off. At about 70 MPH, the tach jumped to 4,000. This time, I don't know if anything I did corrected it. I think it immediately self corrected. My hands were not near the paddles.

Anyone had this little feature appear yet?
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Old 11-08-2013, 07:24 AM
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Re: 2014 Overland 3.6 weird downshift

Never had it happened in my Jeep, but our Subaru with the CVT will randomly decide to engine brake going down steep hills, I am not a fan of that.
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Old 11-08-2013, 08:49 AM
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Re: 2014 Overland 3.6 weird downshift

Quote:
Originally Posted by Bborzell View Post
4,000 miles. Has most recent transmission flash. Everything fine with shifting for last 500+ miles.

Wife and I decided to drive to Reno from Colfax, CA to visit Scheel's outdoor store and have dinner. Long about Emigrant Gap on a long downhill in Eco mode, at about 70 mph, the transmission apparently downshifted and the RPM went to 4,000 ( I later experimented and concluded that 4K RPM was consistent with 4th gear). I think I was in Cruise control, but I tapped the brake in case the cruise has decided to gear down (going downhill)

RPM immediately settled down in keeping with road speed and 8th gear in Drive and we continued on to Reno. Thought I might have inadvertently tapped the DS paddle, but doubt that I would have tapped it 4 times without knowing it.

On the return trip, we were once again on a long downhill near Emigrant gap and this time, I knew that cruise control was off. At about 70 MPH, the tach jumped to 4,000. This time, I don't know if anything I did corrected it. I think it immediately self corrected. My hands were not near the paddles.

Anyone had this little feature appear yet?
This is normal and actually desirable! The truck is intelligent enough to recognize that it is going downhill and it uses the tranny to use the engine brake (known as engine braking) otherwise you would use your brakes to maintain speed which will overheat them and you might lose them at the end of the hill ...
When the rpm increases it shuts the fuel consumption as well .. so you are not wasting fuel ...
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Old 11-08-2013, 09:27 AM
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Re: 2014 Overland 3.6 weird downshift

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Originally Posted by TurboRush View Post
Never had it happened in my Jeep, but our Subaru with the CVT will randomly decide to engine brake going down steep hills, I am not a fan of that.
That must be it! My GC spends its evenings sitting alongside my wife's Outback with CVT. I guess it's contagious but the Outback must just be a carrier as it has never manifested any similar symptoms on its own.
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Old 11-08-2013, 10:06 AM
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Re: 2014 Overland 3.6 weird downshift

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Originally Posted by Bborzell View Post
That must be it! My GC spends its evenings sitting alongside my wife's Outback with CVT. I guess it's contagious but the Outback must just be a carrier as it has never manifested any similar symptoms on its own.
I was simply citing an example of where I had seen similar behavior in a vehicle that caught me by surprise.
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Old 11-08-2013, 11:18 AM
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Re: 2014 Overland 3.6 weird downshift

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Originally Posted by TurboRush View Post
I was simply citing an example of where I had seen similar behavior in a vehicle that caught me by surprise.
Didn't mean to come across sarcastic. Thought I had hit a laugh but hit instead.
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Old 11-08-2013, 11:33 AM
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Re: 2014 Overland 3.6 weird downshift

Quote:
Originally Posted by Bborzell View Post
4,000 miles. Has most recent transmission flash. Everything fine with shifting for last 500+ miles.

Wife and I decided to drive to Reno from Colfax, CA to visit Scheel's outdoor store and have dinner. Long about Emigrant Gap on a long downhill in Eco mode, at about 70 mph, the transmission apparently downshifted and the RPM went to 4,000 ( I later experimented and concluded that 4K RPM was consistent with 4th gear). I think I was in Cruise control, but I tapped the brake in case the cruise has decided to gear down (going downhill)

RPM immediately settled down in keeping with road speed and 8th gear in Drive and we continued on to Reno. Thought I might have inadvertently tapped the DS paddle, but doubt that I would have tapped it 4 times without knowing it.

On the return trip, we were once again on a long downhill near Emigrant gap and this time, I knew that cruise control was off. At about 70 MPH, the tach jumped to 4,000. This time, I don't know if anything I did corrected it. I think it immediately self corrected. My hands were not near the paddles.

Anyone had this little feature appear yet?


Had mine in for repairs about 3 weeks ago, and they also did the most recent trans flash: Since then, mine also behaves similarly. When I leave my house, I immediately have about 1 mile at a decent decline: I'll be going about 30 MPH, and it jumps to 4K rpms. happens about 1/3 of the time. If I don't hit the brakes or gas, it will continue for the whole mile, and the engine sounds pretty damn loud. Dealer says it is the trans trying to engine break to avoid gaining too much speed going downhill. Not sure how much I buy that.
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Old 11-08-2013, 12:15 PM
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Re: 2014 Overland 3.6 weird downshift

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Originally Posted by marosenb View Post
Had mine in for repairs about 3 weeks ago, and they also did the most recent trans flash: Since then, mine also behaves similarly. When I leave my house, I immediately have about 1 mile at a decent decline: I'll be going about 30 MPH, and it jumps to 4K rpms. happens about 1/3 of the time. If I don't hit the brakes or gas, it will continue for the whole mile, and the engine sounds pretty damn loud. Dealer says it is the trans trying to engine break to avoid gaining too much speed going downhill. Not sure how much I buy that.
Which would suggest that the GC knows that it is going downhill. Not sure what sort of algorithm would decide that me going 65-70 MPH on an interstate with a decline would require a drop to 4th (or so) gear. Sounds like a solution in search of a problem.

Sure would like to know if this is a built in thing or an out of whack transmission issue.

EDIT: OK, now I have thought about it a bit more. The transmission knows when road speed increases without adding gas. It translates that to going downhill and decides that the only options left to control descending speed are hitting the brakes or triggering engine braking. It knows that the brakes have not yet been applied so, given the rate of acceleration absent more throttle being applied, it figures that I am daydreaming and it drops to a gear that will reduce speed, but not dramatically. I then come to my senses and touch the brake which transfers engine speed control back to me.

My guess is that this only works in Drive as opposed to Manual. Not sure about Sport though.

Nice to figure out that it is a feature.
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Old 11-08-2013, 12:40 PM
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Re: 2014 Overland 3.6 weird downshift

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Originally Posted by FAST_US View Post
This is normal and actually desirable! The truck is intelligent enough to recognize that it is going downhill and it uses the tranny to use the engine brake (known as engine braking) otherwise you would use your brakes to maintain speed which will overheat them and you might lose them at the end of the hill ...
When the rpm increases it shuts the fuel consumption as well .. so you are not wasting fuel ...
At first, I thought you were making sense until I got to the shutting off fuel consumption thing. That sounded like a Super Eco mode just for downhills..

After thinking about it more, I think you meant it shuts off fuel delivery (same thing, only easier to picture in my mind).

What is odd, though is that I have made that same drive at the same speeds three times and, only on this trip did the downshift occur. Even stranger is that both occurrences happened on runs down the same draw only from opposite directions. Maybe altitude and temperature are factored in.
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Old 11-08-2013, 01:03 PM
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Re: 2014 Overland 3.6 weird downshift

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Originally Posted by Bborzell View Post
Maybe altitude and temperature are factored in.
Wow, these are some smart jeeps!


For me, I would want the acceleration... I am starting from basically 0mph, and coasting downhill. Why should my jeep decide that it does not want to pick up speed, and therefore engine break, and only do it sometimes. meh, who knows.
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Old 11-08-2013, 01:14 PM
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Re: 2014 Overland 3.6 weird downshift

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Originally Posted by TurboRush View Post
Never had it happened in my Jeep, but our Subaru with the CVT will randomly decide to engine brake going down steep hills, I am not a fan of that.
I actually like engine braking capability, BUT only if it is consistent and makes no huge jumps in gearing so it doesn't drastically change the loading at any time.
Reason being that if traction is marginal, it just became a tad less existent.

And, I'd want the option to disable it--where doing that automatically in the snow or similar modes would be a good start.
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Old 11-08-2013, 01:16 PM
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Re: 2014 Overland 3.6 weird downshift

Quote:
Originally Posted by FAST_US View Post
This is normal and actually desirable! The truck is intelligent enough to recognize that it is going downhill and it uses the tranny to use the engine brake (known as engine braking) otherwise you would use your brakes to maintain speed which will overheat them and you might lose them at the end of the hill ...
When the rpm increases it shuts the fuel consumption as well .. so you are not wasting fuel ...
It isn't at all desirable if that changes the loading on the drive wheels on a slippery surface, unless one is a liability lawyer looking for a new BMW budget.

There are those who argue that the worst set of brakes on any modern non-commercial truck/vehicle tend to be better than the rest of the drive train and a heck of a lot cheaper and easier to replace due to the inevitable wear and tear.
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