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How To: Transgo Jr. Shift Kit

90K views 105 replies 49 participants last post by  Stroked06Goat  
#1 · (Edited)
Okay, I know this to has been done to death but thought I would just give another one to demonstrate how easy this kit is to install to compliment all of the other similar threads out there.

Here is how the Transgo Jr. SK comes packaged.
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Drain the transmission fluid. Before dropping the transmission pan get a large drip pan, large cookee sheet or a actual transmission drain pan like shown here. The point is to have something larger than the transmission pan itself. Once the pan is removed trans. fluid will rain down until the process is completed and the pan reinstalled.
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Pull the internal filter down out of its bore. This may require some slight twisting and walking it out of the bore/seal.
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This is what you should be looking up at.
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While the internals are dripping off I took a few minutes to clean the pan. You can see there is minimal sludge in the pan which is perfectly normal. Actually a little more than this is actually normal, my transmission only has 80k miles on it and this is the second time I have serviced it in the 5 years and 25k miles that I have owned it.
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You will get a little more sludge off of the magnet but not much. What you don't want to see is metal peices. That would be bad.
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The pan gaskets are reusable to a point. This is only the pans first time off so I chose to clean it up and reuse it. The filter kits run about $53.00 for the filter and gasket vs. only about $33.00 for just the filter. I chose to just purchase a replacement filter.
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Now back under the truck. Disconnect all of the wiring from the solenoids and the PSM. Be very careful with the locking tabs on these connectors as they tend to get brittle over time and throughout many heat cycles. There are two small wire retainers that need to be temporarily removed to move the wiring harness out of the way. Remove these two wire clips, move the wiring harness and reinstall the two wire clips. These hold solenoids into the valve body and you could drop and lose or damage them if they fall out.
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Reinstall them once the wiring harness has been removed.
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Carefully move the wiring harness out of the way. Be careful to not use force and merely use something to hold it back out of the way. I use a bungee cord to loosely hold it against the exhaust pipe without pulling or tugging on the wires themselves.
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Personally I don't like to have a trail of oil across my shop floor so rather than remove the valve body and hurry across to the bench I have a large pan ready to set the valve body into it. This way I can carry it to the bench and use the same drip pan to perform my work on the valve body and prepare it for reinstallation.
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I prefer to break all of the bolts loose on the valve body while it is still held firmly in the transmission. This is much easier than just removing the ones holding the valve body to the transmission case and then chasing the valve body around the bench while trying to remove the remainder that hold the two halves of the valve body together. Once all of the bolts are broken loose I remove only the bolts that hold the valve body assembly to the transmission so it doesn't fall apart before I am ready for it to.

I leave this bolt until last and remove it when I have ahold of the valve body.
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There is a small pin right here on the shift comb where it attached to the manual shift valve. Be careful to not damage or loose this small pin. Once the last bolt is removed from the valve body, wiggle or walk the valve body off of the dowel pins and turn to disengage this pin from the shift linkage/comb.
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Better view of the pin in previous picture.
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To be continued in the next post.

Mike.
 
#2 · (Edited)
Now we will continue on with the valve body on the bench.

These are your two trim solenoids/valves. These are what we will be removing, replacing and modifying.
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Trim Solenoid "A". Black plastic connector body.
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Trim Solenoid "B". Tan plastic connector body.
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Remove the bolts holding the PSM to the valve body. Make certain all of the O-rings are in place and accounted for. The new version has four O-rings and the earlier version has six O-rings.
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The O-rings seal against these ports. Sometimes the O-rings stick to the valve body rather than stay with the PSM.
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Push inward on the two trim solenoids in order to remove the retaining bracket.
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Once the bracket is out of the way, remove the two accumulators and springs so you don't drop or loose them when handling the valve body. The accumulator goes into the bores with the pocket facing outward and the springs drop into the pockets.
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I drew this layout as a visual reference to demonstrate the old and new parts.
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Both new valves have a small ball that needs to be inserted into the hollow end of the valve.
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Put a small "dab" of either Vaseline or TransGel in to hold the ball and spring in the valve.
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Now insert the small spring on top of the ball.
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Here are the two new trim valves assembled and ready for installation into the valve body. Trim solenoid "A" has the rib in this area.
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Now remove and clean the seperator plate located between the two valve body halves.
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This is where you want to make 100% certain you have the correct holes identified. Use your instructions and count bolt holes or ports or whatever you need to in order to locate the proper holes to be drilled.
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Use the .125" drill bit furnished in the kit.
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Once the two holes are enlarged to .125", make certain to debur the holes. You can use a file or I like to use a deburring bit and then breathe over them with some fine every paper. Then another final cleaning before reassembling.
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Reassemble the valve body halves.
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Here is the assembly ready to be installed in the transmission. Take a good look at this picture as it shows which bolts need to be completely removed to drop the valve body from the transmission and which ones only need to be loosened and can remain intact until you get it on the bench. The two holding the crossover tube can be installed on the bench as they do not go all the way through, I merely was too lazy to grab them off of the cart before snapping the picture.
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It is also easier to gain access to remove the filter seal before installing the valve body assembly. Be very careful here to ONLY engage into the seal and do not scratch or gouge the bore that this seal resides in. This can induce air into your system as it will be possible to suck air through the scratch rather than pull fluid up through the filter.
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Do not forget to reinstall the pin into the manual shift valve before installation of the valve body into the transmission.
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Install the valve body and torque all of the fasteners to 108 in/lbs. I prefer to step up in three incremental steps to the final of 108 in/lbs.
Then install the spring shifter detent. Do not install this too prematurely as it covers one of the valve body bolts that need to be torqued down.
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Install the wiring harness and connect all of the connectors to their respective solenoids. Make certain to reinstall the harness assembly under these two wire retainers.
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Don't forget this connector on the solenoid that is slightly hidden above the other two.
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Install the new internal filter once the wiring is completed and install the gasket and pan. Torque the transmission pan bolts to 18 ft/lbs. Also install a new spin-on external filter while your at it.
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Fill with transmission fluid. I choose to use Mobil 1 Delvac as it is supported by Allison and carries the TES295 specification. You can use Castrol Transynd as well but I use the Mobil 1 in my Allison 3000 series transmission in my coach as well so I only need to stock one.
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I hope that was helpful to anyone thinking about tackling this job on their truck. It really is quite simple but messy so be prepared with cardboard slip sheets or plywood to keep your concrete clean.

Mike.
 
#4 ·
Sub'd, I have the kit just haven't had time to install it yet.


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#5 ·
Great write-up. I have never messed with maintenance on a transmission and it scares me. I will jump into just about anything engine related, but even with your step-by-step I'm not sure I would trust myself to do this without dropping/losing something or screwing something up.

On a side note, since I am so ignorant with transmissions, what exactly is the Transgo Jr kit good for?
 
#6 ·
On a side note, since I am so ignorant with transmissions, what exactly is the Transgo Jr kit good for?
TRANSGO JR

FITS: 2005-2010 6 Speed Allison 1000-2400 series. Duramax Diesel Chevrolet, GMC Diesel/Gas Trucks Heavy Duty, Street, Show & Competition. For 5 Speed Allison use Allison SK.

FEATURES: Corrects/Prevents/Reduces:Goes to neutral under load; 3-4 slip; burned C2 or C3 clutches; sticks in one gear; won't move after extended parking; loss of pump prime; smart clutch control valves for increased durability; SHORT-CRISP-SMOOTH-upshifts and kickdowns. Handles 500 Street Horsepower.
 
#9 ·
No problem. Glad the pictures and write-up helped. I was hoping to take some of the mystery or fear away from installing this shift improver kit in the Allison.

Mike.
 
#10 ·
Sub'd. I have the kit just haven't installed it. I'm also one of the ones worried about messing something up and just not enough time to install it. Your write up makes it look so easy, I'm just nerves about possible messing it up and having to drop money on a trans rebuild.
 
#11 ·
Just follow through the process that I have laid out and you will be fine. The biggest things are to be clean about it so that you don't introduce any dirt/debris into the transmission and when drilling the holes be absolutely sure you drill the correct one. Like the old saying "measure twice/cut once", same applies to drilling holes.

It is a pretty easy and straight forward procedure, not necessarily one to be feared.

After several weeks now after installing the kit I am happy with the changes it made to the shift characteristics. It shifts much crisper and firmer now, not harsh by any means, just crisp and firm.

Mike.
 
#12 ·
subd for next weekends project
 
#13 ·
Sub'd

Great write up...now to buy the Jr and fid some time.
 
#14 · (Edited)
Great DIY! :thumb

I just installed my Transgo Jr (Thanks to Rance for helping) and was gathering info to do a DIY thread until I seen this one.

Here is some more info.




Transgo Jr. Kit, Allison LCT 2000- #T121167















- Debur the holes that you drill in the Valve Body plate -



- Make sure this filter doesn't fall out when splitting the Valve Body -



- Installed a PPE Deep Pan -






Transgo Jr. DIY Links -

http://www.duramaxdiesels.com/forum/showthread.php?t=16176&highlight=Transgo

Trans-Go Jr. write up & Hoot flush

Diesel Place : Chevrolet and GMC Diesel Truck Forums

http://www.duramaxforum.com/forum/how-tos-diy-write-ups/81474-how-transgo-jr-shift-kit-install-allison-6-speed.html

Allison Info -


Fluids -

Approved Fluids

Torque Specs -

http://www.duramaxforum.com/forum/transmission-shop/3379-allison-codes-tq-specs-info.html
 
#15 ·
Some good info. ^^^
 
#16 ·
My kit is in the mail and will be trying this out soon, its great to have all this info here. I'm sure it will make it easier to install.
 
#19 · (Edited)
Welcome....The OP deserves more credit than me thou. :thumb

My kit is in the mail and will be trying this out soon, its great to have all this info here. I'm sure it will make it easier to install.
Here are a few tips to make this much easier.

1- Drain the and remove the pan the night before. Pull the internal filter also, that was the worst of the oil mess for me. I had hardly any constant dripping as others stated the next day while doing the job.
2- Lay down some plastic or cardboard to protect the driveway/garage floor from the oil.
3- Have an extra 8mm socket just incase you break the one you are using. The first Valve Body bolt I tried to remove was torqued to approx 20ft pounds not 9ft foot pounds, snapped my socket in half!
4- Get a friend to help out, it makes a world of difference.
5- Take you're time! Double check everything! There are 9 electrical plugs inside the tranny, torque the Valve Body properly, get the shift pin back into place etc.

This really isn't that hard at all. I've never done any work on a Automatic transmission and it was very easy. Just time consuming is all beings it's very messy and you don't want to rush thru it.
 
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#18 ·
I will be doing this one in the next couple weeks. My kit just came in today.
 
#22 ·
did you happen to get your kit in yet...and if so how is it performing?:thumb
 
#20 ·
thanks for all of the info folks..dropped the pan ..and cracked the bolts to let her drip over night..this stuff is fun!!:thumb:drink
 
#23 ·
No I haven't yet. I should be getting the fluid for it this week then maybe next weekend I will tackle it. Been busy with work and fighting drive line vibrations since the sleeves and pisk installation. I have read up on it though and doesn't seem hard, just takes some time.
 
#24 ·
got home last night at 6 p.m..was out in the shop at 6:05 p.m..walked in the house at 11:19 p.m....LILLY&ALLY is all triple checked...torque to 108 in. lbs...deep pan installed and torqued to 18 ft. lbs..and sitting in shop with 3 gallons of TRANSYND in the pan..drove the Cummins to work because the transgo jr said relearn will take about 2 hours...heres my question tho..since i have a PPE standard that has the relearn option in it and i am on tune #3..do i just hit relearn...or move it up to #4 and relearn ...or move it down to #2 and relearn?
 
#25 ·
Managed to do mine tonight. Pretty good project for Sunday afternoon. Makes a world of difference and I'm only part way into the re-learn.
 
#26 ·
i am enjoying mine..seems to be doing ok:thumb
 
#28 · (Edited)
Was doing mine tonight and the bore on the trim valve A has some scratching and is to tight for the transgo jr valve. Anybody ever have this problem? I'm going to take the lower half of the valve body to my trans shop and see if he can polish the bore and get everything to spec. After the body was out and I found this problem I had to push it the rest of the way into the garage my wife put it in neutral while I was pushing and back to park when I got it all the way in, will this cause any problems when I put everything back together?

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#29 ·
#30 · (Edited)
#31 ·
First I heard of it
 
#32 ·
Just seems to be my luck... shouldn't have even touched the damn thing. It only has 21,000 miles on it.

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