LMM: Built tranny is shot!! (25,000 miles)

Al's max

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Jul 29, 2014
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I need to vent a little. Had my tranny built several years ago by a shop near Houston. Thought it was the single best upgrade I had ever done to a truck. Has never had a single issue until yesterday. After eating lunch truck didn't want to go forward or reverse. Acted like emergency brake was on. Put it back in park and killed it. Restarted and seemed normal. Driving back to work got a P00741 on the ECM and TCM. Temps went to 230! Cranked it today and won't move a inch, just slipping:mad: This was a GMAX-6 kit with a precision converter too. Guess i'm one of those lucky ones:violin:
 

Awenta

Active member
Sep 28, 2014
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Who did it? That's much more important than what's in it.

Sucks either way.

Hopefully it's just the converter. Solenoid code right? Can you command lockup? What's it show for slip?

Sent from my SM-N910V using Tapatalk
 
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Al's max

Member
Jul 29, 2014
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Relentless Diesel. I think it's just one of those things. Not blaming anything just really sucks to only have 4 passes and somewhere around 25,000 miles. The wife has been having a field day with this!!!
 

meshanic

All In Trucks
Dec 9, 2010
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By the sounds of it feeling like the e brake is on & it building heat it could be that pesky E shift valve sticking. I've had several transmissions act just like that & that is what we found. I doubt your trans is toast. Codes in the TCM will inhibit shifts. The Allison won't just take gears if the TCM notices something is very wrong.
 

Bonestock

Active member
Aug 9, 2010
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Kits have come along ways. I had a gmax kit fail me after quite a bit of abuse. This one was from 2010 or 11. The kits had single sided carbolites and the c2 steels would trash the c1/c2 drum. There are better clutches, hydraulics and mods for trans builds today. Het ahold of Evan he will help you out.
 

Al's max

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Jul 29, 2014
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Kits have come along ways. I had a gmax kit fail me after quite a bit of abuse. This one was from 2010 or 11. The kits had single sided carbolites and the c2 steels would trash the c1/c2 drum. There are better clutches, hydraulics and mods for trans builds today. Het ahold of Evan he will help you out.

This was built around 2010, I don't use the truck much and it hasn't been abused much at all. I figured there's better materials now. I'm just an hour and half from Josh H so will be tearing it down soon. Yes fluid was full. Thanks for the replies
 

Mike L.

Got Sheep?
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Your sump filter is plugged. I'll bet you find brown powder in the filter and pan. P0741 indicates no TCC apply.
 

Al's max

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Jul 29, 2014
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Your sump filter is plugged. I'll bet you find brown powder in the filter and pan. P0741 indicates no TCC apply.

Mike what's your recommendation on first filter change after build, and then what do you like to see after that? I'm referring to the sump filter. I will be replacing soon. I'll let you know what I find
 

Mike L.

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I would change the sump filter after the first 20K just because of new clutch fuzz that might come of. We wash them pretty good so I don't worry too much. Most people don't.
Spin on filters should be changed at 15K max; sooner if it is a competition truck. Use only Allison filters as the check valves are much better than after market. They are also cheaper than the chinese crap.
If you find what I'm thinking you're going to find in your sump filter; you need a converter.
 

Moneywellspent

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Dec 27, 2013
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Mike what's your recommendation on first filter change after build, and then what do you like to see after that? I'm referring to the sump filter. I will be replacing soon. I'll let you know what I find

Were they reybestos or alto clutches? When I had my trans built, mike recommended my first spin on filter change at the 1k mile mark, so I did. But I plan on changing my spin on every 5k just to be safe and my internal filter every 20k. Id rather not cheap out on the up keep of a good transmission.
 

Bonestock

Active member
Aug 9, 2010
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Were they reybestos or alto clutches? When I had my trans built, mike recommended my first spin on filter change at the 1k mile mark, so I did. But I plan on changing my spin on every 5k just to be safe and my internal filter every 20k. Id rather not cheap out on the up keep of a good transmission.

I am gonna go out on a limb here and say they were alto's from 2010 time frame.
 

coker6303

Keep Calm and Chive On!!
Aug 6, 2009
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It was a standard gmax6 kit with the precision ML converter. I had the exact same trans built at the same time in my 08 that ran 11's
 

Bonestock

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Aug 9, 2010
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Worland Wy
It was a standard gmax6 kit with the precision ML converter. I had the exact same trans built at the same time in my 08 that ran 11's

Ya I had the same kit as well. The kit held up for quite awhile @ 700hp but eventually gave up the goat. When it did the c3's were melted to the planet and warped like no other. The c1/c2 drum was destroyed from the steels. I believe the Gmax6 kit back then was Alto Carbolites. Mike L or Evan could correct me if I am wrong.
 

Evan@InglewoodTrans

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Aug 5, 2010
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Ya I had the same kit as well. The kit held up for quite awhile @ 700hp but eventually gave up the goat. When it did the c3's were melted to the planet and warped like no other. The c1/c2 drum was destroyed from the steels. I believe the Gmax6 kit back then was Alto Carbolites. Mike L or Evan could correct me if I am wrong.

Yes Randy they were single sided Alto carbonites. They do ok in c4 but usually end up burnt and warped in c3.
 

Al's max

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Jul 29, 2014
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Texas
With the problems others had mentioned about older gmax6 kits I ended up ordering everything new. JoshH tore her down last week and to both our surprise all the clutches looked pretty good. Pan and filters we clean. Clearances were loose but nothing major. Ended up finding a twisted stator support shaft. After some Josh loving this thing is awesome!! It's never shifted so good.