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  #13  
Old 12-21-2013, 08:24 AM
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Re: 8 speed transmission behavior

It will engine brake with cruise control, taking itself from 6th to 3rd, this was through some tight and twisty hills, and yes I was hustling it to see what it could do.
That is not its primary purpose, but I wanted to test after this thread came up.

Maybe I was trying to select the gear too earlier considering the smaller rev range the diesel has, but I don't think so as I kept trying and when it did it was about 2500rpm.
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  #14  
Old 12-21-2013, 10:00 AM
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Quote:
Originally Posted by SNUKE View Post
It will engine brake with cruise control, taking itself from 6th to 3rd, this was through some tight and twisty hills, and yes I was hustling it to see what it could do.
That is not its primary purpose, but I wanted to test after this thread came up.

Maybe I was trying to select the gear too earlier considering the smaller rev range the diesel has, but I don't think so as I kept trying and when it did it was about 2500rpm.
It feels like engine braking but it isn't, it moves the vanes on the turbo to restrict the exhaust to give that effect, which it might be too much stress to shift like that, who knows.
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Old 12-26-2013, 08:03 PM
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Re: 8 speed transmission behavior

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Originally Posted by loveracing1988 View Post
In that respect the diesel might be differnt since you don't have true engine braking. It might be designed that way to control boost and such. Im thinking if you wanted a vehicle you can hustle around like that a grand cherokee with the diesel might not be your best choice.
For me I would like the ability to hold the gear so that I can use the low-end torque of the turbo diesel instead of it kicking down.
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  #16  
Old 01-05-2014, 03:23 AM
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Re: 8 speed transmission behavior

Ok I think I have worked this out at least with kick down. When in paddle shift mode the transmission will ONLY kick down if the engine rpm is at 2000 or under with the currently selected gear.
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Old 01-07-2014, 06:41 PM
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Re: 8 speed transmission behavior

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Originally Posted by SNUKE View Post
But you can't get it to hold the gear selected, it won't hit a rev limiter it just shifts up.
I couldn't get it to drop into second for a tight corner, it would not drop lower than 3rd until it was past the point of use as an engine brake combined with actual brakes.
I wonder what the Hemi does with the same transmission.
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  #18  
Old 03-24-2014, 11:23 AM
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Re: 8 speed transmission behavior

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Originally Posted by 200sxr View Post
Yes WOT is wide open throttle, I guess it is a bit misleading as mechanically there is no real throttle in a diesel engine. Maybe I should just call it "flooring it"

What I have found in manual or paddle mode is the transmission will not hang on to the selected gear. It will down shift as I "floor it" and it will also upshift to the next gear as I approach the programmed up shift engine speed.

I understand the exception is as the car slows down or coming to a stop the transmission would shift down to the appropriate gear.

I really would prefer if I have selected a gear in manual mode the transmission would stay in that gear no matter what, just like a good old manual transmission.
Hi,

I read it somewhere in the owners manual that the GC with diesel engine will not hold the current gear in manual mode to prevent the turbo and the engine from damage. I will tell you what page it is on once i find it.
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Old 03-26-2014, 02:08 AM
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Re: 8 speed transmission behavior

Hi,
Ok I can't seem to find where I read about the transmission upshift by itself when in manual mode to protect the diesel engine and turbo. I did read it somewhere I just need to find it.
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