Anything I need to know before trans swap.

duramaximizer

duramaximizer

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A friend of mine has a 2001 trans, and because of a mishap, the trans case and bell housing cracked and is the trans is leaking fliud. He bought a different trans. Just thought I would ask and see if there is anything I need to know before I start switching out the transmissions. This is a stock trans replacing a stock trans. :(

Also are there any tell tale signs that this trans is out of an 01-02?? LB7??. I just wanted to verify that the trans is right before it goes in.

I can verify it says Allison on the trans and it's for a 4x4.:rofl:

Dextron VI or something else Mike? Anything else that should be done short of building it.

I have heard the converter bolts can be a pain. Any tips trick or tools that I need for that or anyother part of the project. His old trans has a New NSBU switch so I plan on reusing that part.

Thanks Mike or Anyone else. :hug:
 
Mike L.

Mike L.

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duramaximizer said:
A friend of mine has a 2001 trans, and because of a mishap, the trans case and bell housing cracked and is the trans is leaking fliud. He bought a different trans. Just thought I would ask and see if there is anything I need to know before I start switching out the transmissions. This is a stock trans replacing a stock trans. :(

Also are there any tell tale signs that this trans is out of an 01-02?? LB7??. I just wanted to verify that the trans is right before it goes in.

I can verify it says Allison on the trans and it's for a 4x4.:rofl:

Dextron VI or something else Mike? Anything else that should be done short of building it.

I have heard the converter bolts can be a pain. Any tips trick or tools that I need for that or anyother part of the project. His old trans has a New NSBU switch so I plan on reusing that part.

Thanks Mike or Anyone else. :hug:
Click to expand...

Call me and I will give you all the info you need to do this.:D
 
custom8726

custom8726

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I used Dex 6 in mine, Converter bolts are not to bad with 2 sets of hands, pull starter to access the T.C. bolts and have a buddy spin the flywheel with a strait head through the small access hole in the bottom of the trans. I choose to drop the differential seperatly due to the overall weight, which reminds me, get your self a new diff-gasket. Tool to remove transmission cooler lines (Off Trans) or small strait head will do. 3' or so extention to get top bell housing bolts, not necassary, but nice. Thats all I can think of now, its a bit time consuming the first time around but not complicated. Good luck..
 
duramaximizer

duramaximizer

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May 4, 2008
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Just got off the phone with Mike.

Wow, that was fast and easy.


Thanks Mike! :hug:

On Edit: I have 3' plus of 1/2 extension also and a swivel. Thanks Guys!
 
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THEFERMANATOR

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DEX VI in an early ALLISON is a big NO-NO. The early style seals will deteriate rapidly with DEX VI in there. Stick with DEX III or a TRANSYND type fluid.
 
Mike L.

Mike L.

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custom8726 said:
:confused: I would like to hear more on this, since this is news to me...
Click to expand...

It's true. Dex 6 never went through all the necessary testing needed before it was released. Allison hates this fluid and told GM not to use it.
A couple of years ago there was a big freeze in Alberta and a bunch of Allisons went into meltdown. According to my sources at Allison, they found that Dex 6 froze at -40F. This caused the fluid to cook in the converter because the cooler lines were plugged with solidified Dex 6. Another problem was that the fluid going through the cooler becomes lube for the gears when it is returned to the trans. Guess what else melted in the poor Alli?
There was no cold room testing done on this fluid as well. :rolleyes:
Normaly we in the trans industry know what new fluid is coming out a couple of years in advance and read the reports about how it will improve trans operation. Not so with Dex 6. Seems like it showed up over night. WTF
 
custom8726

custom8726

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Mike L. said:
It's true. Dex 6 never went through all the necessary testing needed before it was released. Allison hates this fluid and told GM not to use it.
A couple of years ago there was a big freeze in Alberta and a bunch of Allisons went into meltdown. According to my sources at Allison, they found that Dex 6 froze at -40F. This caused the fluid to cook in the converter because the cooler lines were plugged with solidified Dex 6. Another problem was that the fluid going through the cooler becomes lube for the gears when it is returned to the trans. Guess what else melted in the poor Alli?
There was no cold room testing done on this fluid as well. :rolleyes:
Normaly we in the trans industry know what new fluid is coming out a couple of years in advance and read the reports about how it will improve trans operation. Not so with Dex 6. Seems like it showed up over night. WTF
Click to expand...

Thanks for the indepth resonse Mike:thumb: I never was aware of any issues running dex 6:confused: It is in my LLY and our LB7 currently and knock on wood has been fine thus far. I have a feeling after the dual fuelers and twins go on the LLY the trans will be due for a re-fresh shortly after;), guess I will switch to something else at such point:D
 
THEFERMANATOR

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Also I know ALLISON released a bulletin about the viton seals in the earlier transmissions not being compatible with DEX VI and it would cause them to harden and leak shortly after switching to DEX VI.
 
duramaximizer

duramaximizer

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Thanks for the FYI.

No more Dex 6.

Anyway, The trans the guy got to replace the current one is an 01, so everything should go as planned. Thanks A Lot guys. You saved me some trouble again. Make this a sticky in the trans section. This is vital info for owners. :)
 
LBZ

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Well if Dex VI is junk, what do you recommend us 6 gear Ally guys should be using?
I hope to be building a trans soon........;)
 
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2003 duramax

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Just just to add im sure someone told you but for intalling the conveter bolts i put some oring grease on the head of the bolt so it would not fall down in the bell housing.
 
duramaximizer

duramaximizer

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May 4, 2008
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That top transfer case bolt is a PITA if you don't have a stubby 15mm, or a short ratchet, or some sort of flex wrench. That was my only real trouble. I did it in 6 hours with a little help from the guy I am doing for (rotating the converter etc), I went slow and made sure I knew where everything went. I also had to run to my house 10 miles away to get tools once, since my friend just bought the property with the lift and has no tools. Oh and a stop at Subway for some food. :thumb:


Only problem we found so far is the adapter housing is also cracked, so the fly wheel/flex plate has to come off.

I am have a new transfer case / ally gasket too.

Anyone have an adapter plate forsale? PM me. I may call Mike tomarrow.
 
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