How to Install a TransGo TF-3 Manual Valve Body Kit in a A-904

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    Tearing into an automatic transmission can be kind of intimidating. For most, it seems like something that has to be done by a certified technician, or perhaps a wizard.

    I made this pictorial in hopes that it will show you that you don't need to be a master of the dark arts to do this modification. All you need is a few basic tools, and maybe a shot of whiskey for a dose of courage.

    Installing the TransGo tf-3 manual valve body is a very simple task. It's just unfortunate that the instructions they provide can be a bit confusing.

    It's important to note that this is not a perfect step-by-step for every torqueflite. There have been small changes over the years and across platforms. Because of this, I highly suggest that this guide be used as supplemental information along with the kit instructions. TransGo makes notes of all the small differences, and what needs to be done due to these differences.

    With all that out of the way, let's get started!


    • First step is to pop off the e-clip on the throttle pressure shaft. I just use a flat-blade screwdriver.

      Once the clip is removed, you can remove the rooster-comb (The thing with a "K" and an "E" stamped on it) and slide out the throttle pressure shaft (the thing that the clip was on).

      Pretty simple, right?

    • When you remove the rooster-comb, this ball will pop out. It goes in the little hole above and to the left of my finger in this photo along with a small spring.

      Set these aside for now.

    • Here's the parts you should have removed by now.

    • Next thing you want to do is remove the shift valve piston.

      The piston is the part sitting on the red towel, and it comes out of the hole under the finger on the left. This piston will be discarded.

    • Now remove this bracket.

      There are three screws holding this on. Be careful! There are springs under tension being held back that will want to liberate themselves once the bracket is off.

    • Here I've already removed one screw, and am removing the side screw.

    • Here's the third screw on the other side of the bracket.

    • Here you can see the bracket once it's removed and the two springs.

    • It's now time to split the valve body.

    • There are 13 screws you need to remove.

    • Feeling nervous? Don't worry, it's easy.

    • Here's the inside of my valve body. Yours should be similar though there may be slight variations pending on year and model of car.

      Make particular note of where all those little balls go!

    • This is how I keep them organized. Just used a bit of Styrofoam left over from my torque converter packaging.

      However you go about this, just don't lose them!

    • Next up, you're going to want to use a large file and file a groove directly across this hole. File approximately half-way through the material here.

    • That wasn't so bad, was it? Be sure to clean out any filing after each step that involves material removal.

    • Now grab the "mumbly peg" that came with the TransGo kit. Use it to hold that little spring-loaded ball in place (with the spring inserted of course!)

    • Here's how it should look.

    • Install the new shift valve piston (the one that came with the kit) and reinstall the rooster-comb and throttle pressure shaft.

    • Be sure to get the little arm of the rooster-comb into the slot in the piston.

    • Now we're going to check the piston stroke. Now click the rooster comb all the way down so that the new piston is as far into the valve body as it will go. (It's not all the way down in this picture)

    • See how the piston is visible through the valve-body passages?

    • You want to make sure that the piston face that I'm pointing at is within .03" of being flush with that passage wall.

      If you need to move it, do so by bending the little arm that goes in the slot at the end of the piston.

    • Now you're going to want to remove this piston and set it aside.

    • You're going to need to drill a hole through this wall beside the slot (see where I'm pointing with the screw driver?).

      Use the tiny .046"drill bit that is included with the tf-3 kit.

      You'll want to be careful here. It is a pain in the dick to remove a broken drill bit... Go ahead. Ask me how I know. :(

    • Now you need to remove the TV piston. You can see it in the previous picture right above the new shift valve piston that we already installed. The next picture also shows where it it.

    • Location of the TV piston assembly.

    • Now you need to take the inner-most piece of the TV valve piston and grind down the small end to about 9/32" in length.

      The instructions for the kit has a scale picture you can use as a guide.

    • Here it is after being shortened.

      I just used die grinder with a coarse sanding pad. It will get quite warm so be sure to have it secured in some way that will not damage it. I used this little spring-clamp to hold it while grinding.

    • Now replace the spring that goes in the middle of the tv assembly and put the whole assembly back in the valve body.

      The kit has both a pink, and yellow replacement spring. You want to use whichever one matches yours most closely. For me, it was the yellow spring.

    • Now take the 3/16"drill bit that came in your kit and the drill depth spacer springie thing. You want the drill bit to only stick out 7/16".

      Your kit comes with a little paper measuring gauge to help set this.

    • Install the drill guide plate as shown. Drill through the hole in the plate, using the springy spacer thing to manage the depth.

      My valve body already had a hole here, but I still used the plate and drill bit to open it up to 3/16".

    • Here's what it should look like when you're done drilling.

    • Remove this plate. Be careful! There is a spring in there.

    • Once you've removed the plate, you can remove the 1-2 governor valve.

    • Here is what the governor valve looks like. You're going to need to modify it as shown in the instructions (page 2, step 5)

    • Here's what it should look like when you're done. The instructions say it can be done using a grinder. I didn't want to fiddle with it, so I just had a machine shop turn it on a lathe.

    • Now you need to remove these three screws and the plate and aluminum part they hold on.

    • This guy is also spring loaded so again, be careful.

    • You don't need to disassemble the cast aluminum part that you removed so just set it aside.

    • Now you're going to replace this spring with the one in the kit (pictured).

    • Now you're going to need to do some drilling on the plate.

      instructions explain which holes need to be drilled. You also may not need to drill these. It depends on your specific valve body so consult the instructions on this.

      In this picture, I'm pointing at the first hold I need to drill. You will use the bit that was included with the kit.

    • before drilling the plate, you'll need to remove it.

      There are four screws that hold the plate onto the valve body.

    • First hole drilled.

    • Second hole drilled.

    • Third hole drilled.


    • Last hole drilled.

    • Back to the valve body.

      Using two of the bolts that held the valve body in the transmission along with a crew that came in the kit, you need to align this place and drill a hole at either end of the slot.


    • I forgot to replace this and had to take the valve body apart when I was done. :(

      I'm holding the old style barrel type that was in the valve body. The conical replacement is the new style and a direct replacement for the barrel type.

      Your valve body may or may not have this part.

    • Now it's time to button this back up.

      Be sure to thoroughly clean all the metal filings and any sludge before bolting it back together!

      First, reinstall the plate.

    • Put all the little balls back where they came from.

    • Install this plate using the screws included in the kit.

    • Install these two plates as shown.

    • Use one of the screws from the kit and a washer.

    • Now for some adjustments.

      You want to back out the allen crew here...

    • Until this spring retained plate is just flush with the bracket.

      You'll also need to adjust the TV screw, but I forgot to take pictures of that. The instructions detail how to do it.

    • Now let's take short break from the valve body.

      I just used a hammer to tap this plug into the transmission.

      The instructions say to use a 5/16" punch, but the plug kept getting stuck on the punch when I tried that.

    • Back to the valve body. You should have it all back together now.

    • Now would be a good time to replace the seal that goes around the throttle pressure shaft.

    • No more leaky leaky!

    • I'm using the felt filter that came with my rebuild kit. Saving the mesh filter for after my first fluid change.

      If you install the mesh filter, don't forget the gasket.

    • Just bolt it back on! (Not shown was replacing the accumulator spring but that's very simple.)
    • Now give yourself a pat on the back, crack open your adult beverage of choice, and marvel at this sight which perfectly sums up your own mechanical aptitude!

      So there you have it. It wasn't so bad, was it?

      Now crawl under your car and get started! :D

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