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Discussion Starter · #1 ·
So today I slowed down to pull off the road and in to my drive way. I slowed down, almost to a stop but not completely. I think that I was in second gear, but the reaction of the truck was sluggish (almost as if I was starting from a stop in 4th or 5th gear like the trans did not down shift at all). The RPMs also climbed up but no movement. Then when I finally got moving, there was a loud clank that sounded like it came from the driveshaft. I have no idea what happened.:confused: The truck has felt like it was sluggish almost like it did not down shift before as I have been in the same spot pulling in the drive way, yet I have never heard a pop before. Any know of anything as to this? :help
 

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Discussion Starter · #2 ·
Got any ideas? Trans is really getting on my nerves. BTW I have only limped my tansmission once, and that was 1 week ago. But it has done this before that.
 

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I'm not sure, but mine has done something similar. I think you may just be hitting that point when the truck wants to shift between first and second. So as your stepping on the gas the truck is revving, but not moving till it hits the right RPM's. So if you were revving quick it may have hit 2nd hard.
But then again, maybe I'm just making my self feel better, telling myself this. :eek:
 

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Stupid Has The Balls
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So as your stepping on the gas the truck is revving, but not moving till it hits the right RPM's. So if you were revving quick it may have hit 2nd hard.
But then again, maybe I'm just making my self feel better, telling myself this. :eek:
Well to help you feel better what you are thinking is true. Granted its rare because the point at which it happens is quick and precise. Since the shifting is done electronically the Allison will want to shift into first because you are slowing down but at that one point as it is about to shift and is currently out of a specified gear you hit the gas and now it has to decide what gear based on throttle position and how fast you hit the pedal. Just creates a little lag and when it locks into gear it'll give you a good clunk since the rpms are higher than normal for the shift pattern
 

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Well to help you feel better what you are thinking is true. Granted its rare because the point at which it happens is quick and precise. Since the shifting is done electronically the Allison will want to shift into first because you are slowing down but at that one point as it is about to shift and is currently out of a specified gear you hit the gas and now it has to decide what gear based on throttle position and how fast you hit the pedal. Just creates a little lag and when it locks into gear it'll give you a good clunk since the rpms are higher than normal for the shift pattern
WOW thats a mouthful:drink
 

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The Good Son!
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Well to help you feel better what you are thinking is true. Granted its rare because the point at which it happens is quick and precise. Since the shifting is done electronically the Allison will want to shift into first because you are slowing down but at that one point as it is about to shift and is currently out of a specified gear you hit the gas and now it has to decide what gear based on throttle position and how fast you hit the pedal. Just creates a little lag and when it locks into gear it'll give you a good clunk since the rpms are higher than normal for the shift pattern
I have had this happen on all three of my DMax's. Usually when breaking hard and then hit the throttle. For example being in a hurry catching a red light and braking hard as to not blow the light and then the light turns green and wot. My driving techniques have since changed and the problem never occurs anymore.
 
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