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Truck Down Shifting ....help

2516 Views 13 Replies 8 Participants Last post by  duratothemax
Someone please help me. When i role into the throttle after 70mph. Truck down shifts and won't go back into o/d. I have to put it in neutral, then back in drive and it will work fine. I have a 200hp program in it right now...anyone no why this is happening, and how do i fix it?
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I would say that you are limping it, but since it will shift after going into neutral I would say try changing your fuel filter first.
Stock tranny?
I changed the filter last week and yes the tranny is stock. Just looking for more up grades for power. I got 5inch put on today, took off the stock tires put on 20s. That knocked the wind out of the power when i changed to the bigger wheels. I was thinking about putting on a methonal injection. But no since if the tranny is at it limit with the power i'm putting to it. Any suggestions would help. thank guys.
you are about 100 hp over the tranny's limit with the programming aready. Stock tranny will only hold about 90 hp (180 ft/lbs tq) over stock. Think about it, you increasing your hp by 200 and that equates to about 400 lb/ft of torque. That nearly doubles what you have stock. You have any codes? I bet you have a P1093. Start saving for a suncoast or ats tranny and torque coverter....you have to pay to play.

It is weird, normally when you limp the tranny, the only way that you can reset it is to shut the truck off and restart. You are slipping 5th gear pretty hard though if you are programmed to the 200 hp setting.
I wouldnt reccomend doing this to the tranny any more. It doesnt sound like its going into limp mode but your definatly confusing the computer bad. Possibly slipping it and its forceing downshifts instead of limping. Id say cut the power back to 50hp or less and be easy untill your ready for tranny upgrades.
None of this started to happen until i put those damn 20inch rims on it. The computer and the tire size are not getting along. Keeps throwing codes on for the tire size....And the truck has slowed way down. I'm so disappointed....I'm about ready to put a 100hp shot of gas on it and call it a day...
it is your programmer clear your codes and set it back to what you have it at with no de fueling the de fueling messes your shifting up somthin fierce
Someone please help me. When i role into the throttle after 70mph. Truck down shifts and won't go back into o/d. I have to put it in neutral, then back in drive and it will work fine. I have a 200hp program in it right now...anyone no why this is happening, and how do i fix it?
I think you already answered your own question.

And yes, an allison can "slip back into 4th gear" without doing the typical "full 3rd gear limp to hydraulic-default with check engine light"
I'm just curious becuase on the autoguide app it says you have a stage 4 tranny... If this is the case it shouldn't be the transmission limping but rather a fuel issue possiblely running the 200hp tune and no lift pump...


Sent from my phone
talk about bringing back a dead thread...the last post before today was nov 11, 2006! I think this is the oldest one brought back so far.
wow im an idiot, I didnt even read the original post date. :D
wow im an idiot
Quoted... since its the first and last time it'll ever be said by Ben... ;) j/k man.

Sent from my old skool Droid
Quoted... since its the first and last time it'll ever be said by Ben... ;) j/k man.

Sent from my old skool Droid
:D :p
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