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Alligator Performance Transmission Coolant hoses Kit Installation

Marauderer

Grumpy Old Cur***geon
Messages
860
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Location
Powder Springs, GA
Let me first say there are real nice quality other kits on the market but I think this one is unique and so far I really like it.

Out of the box the kit looks like this.
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As usual you have to start somewhere and I started by removing the grille. On the GMC there is one bolt and six snaps that hold it on. But first remove the cover taking off the 6-8 plastic snap pin retainers off and the bolt for the grill.
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More later

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Next pop the two snaps on the outer ends of the grille both sides and then the four main snaps then lift out. Kinda looks like this after you get the grille off.
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I then removed the air filter box, the plate under it, the bracket under that, and the CAC (Charged Air Cooler/Intercooler) hose on the discharge side of the CAC so you will have access to the hoses and fitting going into the radiator trans cooler.
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Next I removed the cooler lines from the transmission. Remove the black caps and then use a blade screwdriver to remove the clips holding the aluminum hoses into the fitting and then pull the hose out.
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I had a problem removing the upper line return from the cooler as I have the DE Down pipe and DE QT Turbo back 4” exhaust and the upper line needed another 3/8” or so of clearance to remove. So it seemed the easiest thing to try was to remove the fitting in the transmission. A 32 mm wrench worked fine but maybe a slightly smaller one or US size might have been better. A friend told me that is was a 1 1/4" size. Anyway, I backed the fitting out and was able to move the line around and get the fitting and line loose. Side bar, have a drain catch available of fluid residue in the line and lines to be broken. I also removed the supply connection quick fitting at the same time.
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Next I removed the lines from the transmission cooler and the threaded fittings also. Be careful when loosening the fittings as the aluminum cooler is very soft and a counter torque is necessary to prevent twisting the ends of the cooler. Also there could be additional fluid drainage from the fittings at the cooler and the other ends at the transmission. Did I mention that I don’t like loose transmission fluid. It can get real messy. The fitting that you use in the trans cooler are the 90* short fittings.
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Now I replaced one line at a time and the first one I did was the outlet of the trans cooler back to the transmission (upper one). The fittings in the transmission, radiator cooler, and transmission cooler I left loose and after hooking up the hoses I did the final alignment and then tightened the fitting both the hose and the threaded body fittings. When removing the old lines I cut the flex hose and they came out so much easier with no hassle. After I replaced the return hose I removed the old and then replaced the outlet of the radiator to the transmission cooler line (straight fitting on one end and a 90* fitting on the other). I left all hose and cooler/trans fittings loose until the final alignment (after all hoses installed). And last I removed an replaced the outlet of the transmission to the Radiator Trans cooler line. I ended up removing the outlet of the radiator to trans cooler line at the radiator so I could get the lower radiator cooler line installed and after I got it final installed (all fittings tight) I reinstalled the CAC to ENG hose and then did the upper radiator fitting alignment and tightened.
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I then went to the inlet of the trans cooler and did the final tightening of these fittings (2). Remember to use a wrench to counter torque your tightening so you don’t bend and/or distort the trans cooler.
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More later
 
When installing the threaded fittings into the transmission (there are four 90* fittings in the kit of which one is about ½” longer) install the longer fitting on the bottom of the transmission as the shorter one will not work due to interference.
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When installing the fittings in the radiator use the two with the large washers. The straight one goes in the upper bung and the 45* fitting in the lower bung. You will notice in the kit there was two extra o rings. Install these on the fittings that go into the radiator. That means there will now be two o rings on each fitting. This needs to be done as if you use just the o ring that is on the fitting the large washer will prevent the fitting from seating the o ring in its proper area and the fittings will leak. (Alligator told me that it wasn't necessary and they haven't had any reports of leakage with over 30 installations so far)

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Last I went back and made sure there wasn’t anything sharp rubbing on the hoses at any place. I started it up and let it run a few minutes and checked for leaks before reinstalling everything so I didn’t need to do double work. There is a bracket that hold the hard lines next to the engine block that is a bit of a pain to remove. It has a 10 mm nut/bolt on it that has to be removed to get the old lines out. Also the lines from the transmission are routed different than the factory hard lines but I didn’t have a problem with that.
 
I found this thread using a search engine and I'm glad I did. I have the Alligator kit on the way and these instructions should prove immensely useful. Alligator should pay you a few buck and reference this site for installation instructions.
 
Welcome to our Forum! :welcome2:

Barry did do an awesome writeup on this install! :thumbsup:

I would assume that their have been no leaks since this was done Barry?
 
None! I did find that a hose had been rubbing on the center link and I used a tie wrap to pull it up.

Tbrowne, I would not be surprised if there was a copy of my article in your kit Alligator are great folks to deal with and have lots of real experience folks to help you. I mostly talk to Holton and Jason both a very knowledgeable on the Dmax/Allison setups.
 
Damn, that is a really Nice Kit.

I got the Replacement one with the Braided Lines and Russell Fittings, but it's still Leaking...very Slow though, but it's still Leaking.

May have to get this Kit next.
 
Are there threads in the trans, radiator and cooler connections for the new threaded fittings? I wouldn't expect to find them since the factory connections use clips and are threadless.
 
Are there threads in the trans, radiator and cooler connections for the new threaded fittings? I wouldn't expect to find them since the factory connections use clips and are threadless.

Yes, the factory clip fittings are screwed into the rad, trans and cooler.
 
I really need to do this

Mine leaks but I have not done anything about it yet. The mechanic at the dealer mentioned it years ago and mentioned replacing the lines for x amount of dollars. I told him if he could not guarantee that the factory lines had been improved enough to prevent it leaking again, I would just go to plan B, which would be something like this kit.
 
Is your lines leaking or weeping? As long as you have had your truck and the miles you have put on it, it really looks good. And you don't want to rush into anything you don't have to. Hehehe!!
Weep up front when it's cold. They don't leak in summer. I replaced the main return line with a factory one a good 200k ago.
 
Then let it ride and go spend your money on something else unless you just have to much money and want to squander it or send it to me.:rolleyes: Hehehe!!
 
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