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Hi I have an lb7 2001. This might be a stupid question but it should be a 5 speed Allison right? Well when I was driving I counted 6 gears? I did this 3 times and got 6 gears each time... So is it a 6 speed? Help me out
 

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the transition from 5th with the TC unlocked to locked sounds like a gear change...believe me you have a 5spd
 

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Bet you're feeling the torque converter lock, probably in 5th gear. RPM drops a bit again even though no shift takes place.

Edit: Damnit, Beat by seconds the ONE time you answer someone seriously:rolleyes:
 

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LOL I was quick on the draw
 

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What they said ^ .....Your taking notice of the torque converter lock up, which seems like another shift of gears but its not... at at 70 mph you should be somewhere around 2k rpms.....should by chance if you bought your truck used and someone put in the 6th speed kit it should be around 1700 or so rpm....but most likely it just your TQ converter locking up....
 

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While your driving along and feel it shift into 6th gear tap on your brakes while you keep your other foot steady on the gas pedal.I bet you will feel what you think is 6th gear downshifting to 5th its the TC unlocking.
 

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If you have the 6 speed, the RPM will drop about 300-350 RPM, when you shift from 5 to 6. The torque converter will usually drop less than 100 RPM when it locks.

You are feeling the converter lock-- for your "6 speed"!
 

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Discussion Starter #8
Ok haha I knew there's no way the previous owner put any aftermarket on it. They used it as parts runner. Thanks for the help. While I'm on here I might as well ask... I have ppe soon going to EFI live but I have the famous 5th gear shutdown that puts it locked into third when I accelerate too hard on the interstate. Any reccomendations on kits to prevent this that's reasonably priced? Keep in mind I'm 17 and work for 8.25 per hour...
 

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Being a little lighter on the loud petal. :thumb
Sorry, but in your situation you can't afford to blow sh#t up, right? They'll take a beating but you'll be playing with fire if you go too far.

Other answer. TransGo kit. But from how I understand it you gotta drop the tranny. Not very expensive (Don't get the Jr. thats the 6-speed version) just a little more work :thumb

Edit: See my sig? Believe me I'd love to be pushing some mods but right now, but if I blow it, I'm DONE
 

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ya the famous shut down is called limp mode. which could mean you transmission is on the way out. the stock allsion doesnt like 80 extra horsepower and usually slips between 4th and 5th
 

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yep be careful with that allison
 

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You felt the torque converter lockup after 2nd gear(if you were getting on it,or you had it in tow/haul mode)....a five speed trans will shift four times,and a six speed will shift 5 times.I'd be willing to bet you felt the TC lock up and mistakenly though that was a shift..
 
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