ALLISON TRANS PROBLEM

HEATHN · December 5, 2005

I have a 2004 duramax w/an allison trans. i have continues problems w/ the trans. shifting from 4th to 5th gear(passing gear)at full throttle. I am running a banks 6-gun tuner. The check engine light comes on & the trans will not shift into 5th gear until i stop, kill the motor & restart. the dealer replaced the shift silonoid but the problem still exist. Does anyone have any suggestions or comments.

Machine · December 5, 2005

I have a 2004 duramax w/an allison trans. i have continues problems w/ the trans. shifting from 4th to 5th gear(passing gear)at full throttle. I am running a banks 6-gun tuner. The check engine light comes on & the trans will not shift into 5th gear until i stop, kill the motor & restart. the dealer replaced the shift silonoid but the problem still exist. Does anyone have any suggestions or comments.

<{POST_SNAPBACK}>

Sounds like you're "limping" the allison with the extra HP from the Banks. Does it do this in stock configuration? Levels 5 and 6 on the Banks could be pushing the stock limits of the Allison causing it to go into safe mode. Level 6 is about 125 additional HP, right? If so, and if that's what you're running when the Allison does this, then I bet that's the issue.

HEATHN · December 6, 2005

I have a 2004 duramax w/an allison trans. i have continues problems w/ the trans. shifting from 4th to 5th gear(passing gear)at full throttle. I am running a banks 6-gun tuner. The check engine light comes on & the trans will not shift into 5th gear until i stop, kill the motor & restart. the dealer replaced the shift silonoid but the problem still exist. Does anyone have any suggestions or comments.

<{POST_SNAPBACK}>

Sounds like you're "limping" the allison with the extra HP from the Banks. Does it do this in stock configuration? Levels 5 and 6 on the Banks could be pushing the stock limits of the Allison causing it to go into safe mode. Level 6 is about 125 additional HP, right? If so, and if that's what you're running when the Allison does this, then I bet that's the issue.

<{POST_SNAPBACK}>

[/quote

Thanks machine, That seems to be when it is happening. I guess i need to back off alittle bit.

dewfpo · December 6, 2005

I've heard that the Allison can handle about 90HP above stock before it starts to slip and then the TCM will LIMP it. There are modifications its for your Allsion so this won't happen.

DEWFPO

Machine · December 6, 2005

By installing a Suncoast Stage 3 / 4 you can go way beyond the 125 HP limit that usually limps fifth gear in the Allison. It'll put you back over $2K but it's what you'll need to start stacking and/or tuning for the real big HP.