allison transmission Codes P0729, P0735, P02723

cb197cj5

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I have a 2006 Duramax with the Allison in it. I got a call from the shop today that the transmission had the codes P0729, P0735 and P2723. I ran it for the first 80,000 miles and one of my salesmen has taken it to 120,000. What caused a 5th and 6th gear sync problem on a non chipped stock truck? I did put 265 tires on it. . .That is the only modification from stock. If I do have to put a new transmission in it, what aftermarket beef up parts should I put in to stop this from happening again?
 
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Mike L.

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Speed sensor problem is where I would look first. P0729 is 6th gear incorrect ration, p0735 is 5th gear incorrect ratio. P2723 is a tie up. ( 2 gears at once ) transfercase is the next step after speed sensors.
 

cb197cj5

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Thanks MikeL transfer case wins the prize. The bushing that goes around the yoke coming out of the Tcase to the front of the drive shaft has been spit out. Just a transfer case rebuild? Any one make beefed up tranfer case kits?
 

Mike L.

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Ok guys needin help.....i have an 03 duramax with the 5 speed allison....ive had a chip on it since ive had it no problems....recently i changed the oil in the transmission all of a sudden it started throwin 0700 and 0735 and limpin 5th...pull the chip off its fine! Whats goin on?

You beat the snot out of it. Probably burnt clutches.
 

WolfLMM

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Ok guys needin help.....i have an 03 duramax with the 5 speed allison....ive had a chip on it since ive had it no problems....recently i changed the oil in the transmission all of a sudden it started throwin 0700 and 0735 and limpin 5th...pull the chip off its fine! Whats goin on?

You don't say.
 

56taskforce

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I think I am tested every time I am here :roflmao: or I feel like I should be tested every time I leave here.
 

ALLY Fox

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My vote: burnt clutches. You can't tell by having your transmission "looked at" unless your expert looker has Xray eyes just like Superman does. Did you send the fluid out for analysis? What tests were performed to reach that conclusion?
 

Chevy1925

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My vote: burnt clutches. You can't tell by having your transmission "looked at" unless your expert looker has Xray eyes just like Superman does. Did you send the fluid out for analysis? What tests were performed to reach that conclusion?

i dunno, i mean, i have them there calibrated eye balls. every time i look down i see 12". strangely the wife doesnt agree but i feel her eyes are not as calibrated as mine :D
 

Mike L.

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P0735 can be caused by speed sensor, transfer case ( loose tone wheel ) or damaged clutch pack. If the problem is speed sensor or transfer case; removing programmer will not make a difference. It will still act up. If the clutch pack is weak; removing power can make a difference. If you had a weak trim solenoid; there would be more codes and other gears slipping.
 

WVRigrat05

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My friends 07 classic just did the same thing, tail end of the transfer shit the bed, I wanst there but the shop told him the driveshaft was stuck and they had to put a new yoke on. New transfer and it was good to go.
Greenmax, time for a new trans, fresh fluid is slicker than burnt fluid.
 

Mike L.

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Ok dont b a jerk about it.....all i was told is they pulled it off everything looks fine. I had no problems with it until they changed the oil in it. And i have absolutely no trouble out of it as long as the chip is left off. The transmission guy said it could b something wrong with the chip....it will also keep it from starting right. But it just started doing this out of nowhere. If ur not gonna answer respectfully keep ur two sense out. I am asking for help for a reason!

Seems like everyone here is pissing you off. Try another forum.
 

WolfLMM

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Do you think your cute? I just wanted to see what you guys thot......

Dude, you ran a "chip" for no telling how long and your Trans started limping in 5th, then you pull the chip off and the trans holds magically..... It didn't ever dawn on you that you put too much power thru the trans and hurt it? Come on. I'm sorry for being smart, but damn we see threads like this everyday. And really it's common sense. Your trans is hurt, no way around it.
 

WVRigrat05

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I killed my 5 speed on a 90 horse tune and then destroyed it on a 150 tune. My LMM converter slips on a 60 horse tow tune and I've only had it over 100 horse tune twice. And I've been fairly nice to this truck. They just don't like power. And fwiw my lmm has never had any metal or clutch shavings in the filter.
 

WVRigrat05

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Burnt oil is not normal. Even if the fluid is still reddish doesn't mean it's still doing its job. That's why I change mine every 25-30k instead of 50k like the manual says, esp. If your running a "chip" or running larger tires or towing a lot