Grabberman
Well-known member
The time has finally arrived. After running my twin stick setup for a year I am fairly convinced that it will hold up for the long haul.
I have promised to do a write up on how I made my twin sticks if I ever had to tear my T-case apart again, and the time has come! So sit back, grab a cold one and enjoy!
IMPORTANT: You must have the center detent ball removed from your t-case. If you already have that removed then there is no need to fully disassemble your t-case, but if your case still has it in place you must split the t-case to remove it. There are instructions for this elsewhere on here so I will not cover this.
Here is the reason I had to dive into my t-case, on a recent wheeling trip my driveshaft was crimped into the extended position and the stress from driving it out of the rocks caused the front output shaft to shear.
I also had some bearing noise I wanted to investigate as well.
To get started, remove the stock shifter and set it aside.
Next remove the front output housing from the t-case. There is no need to remove the front flange. I do however recommend draining the gear oil prior to this step or you will have a big mes on your hands (and everywhere else!)
Now clean everything up so you can actually see what you are working with.
You should have something like this, but with the flange on it.
Next you need to drill a hole for the new shift linkage centering bolt.
First drill it 13/64 or a #7 so it is the proper size for 1/4 20 tap. (double check my bit sizes, they may be wrong)
Line up the center of the hole on the casting line in the shift tower, and on plane with the stock shifter locating tabs.
Carefully drill through both sides of the shift tower. making sure everything is square and lined up. (again use the casting lines as a reference point)
After drilling through both sides, use a 1/4" bit to open up the first side only, and then double check that your tap will slide all the way through, you man have to open the hole up one additional size to clear the tap.
Carefully tape the far side of the hole. Use care because it is aluminum and it is thin where it is being threaded.
Now it is time to start making pieces and parts.
Out of 1/4 steel make 2 pieces that mimic the end of the stock shifter as shown in the pictures below. the "ball" area needs to be smaller than the stock ball to clear the locating pins in the shift tower. Make the top long enough to attach some type of shift lever to later.
I'm sorry that I don't have a pattern to post or even a better image, but you should be able to get the idea.
You also need to make a couple of spacers, I used aluminum, due to the fact that it was easy to work with and it was on hand. you can see the overall thickness in the picture below, and the outside needs to be radiused to fit inside the shift tower.
You also will need some nylon washers from the hardware store, I think mine came from Home Depot. They are approx 3/4" diameter, and .060 thick. I used 4 one between each spacer and the shift arm, and 2 between the arms.
To ease assembly I made a slight modification to my original design (I wish I had [idea] sooner) I drilled the center holes of my shifter out large enough to accommodate a sleeve that fits through everthing, and holds it together as one piece. It makes Assembly MUCH easier.
Oh, the piece I used was a Bick pen, just cut a piece small enough to fit inside the shift tower.
Here is everything assembled and ready to go together.
:-[Please note that from this photo on I assembaled things incorectly. If you look at the arms in the pictures you can see that the top arm has been clearenced slightly. That is suposed to be towards the t-case, not away from it.
After I assembaled everthing I realized that it wasn't fully engaging in low range and that my shift levers were pointing the wrong way so I hade to bull the shifters out and rearange the pieces. DOH!
Here is what it should look like installed in the housing (note, the output housing can not be put on the case with the shifters installed)
If you look closely at the above pic you will see where the shifter arm needs to be clearanced to have enough room.
Here is a shot from the frontside where you can see the new 1/4" bolt running through the shift tower.
Everything reassembled. This is where I realized that I screwed up and had my shifters wrong. It is slightly confusing to me because I have changed them 3 different times since my original installation, sometimes with a torch and sometimes with a welder.
I would reccomend that you incorporate into your design the means to bolt the shift handles onto the new shift rods. I originally planned to do this but got to excited to try it out and just welded on two pieces of rod. It hasn't bugged me enough to change it yet.
I also reused the stock shifter boot without any modifications, and I filled the area below the boot with grease to help keep the water and dirt out, it works OK, but is not perfect. There is a vendor on here who is supposedly working on a boot for a twin stick shifter, but I haven't been able to getScott er I mean him to send me one yet.
Feel free to ask any questions you have,
I have promised to do a write up on how I made my twin sticks if I ever had to tear my T-case apart again, and the time has come! So sit back, grab a cold one and enjoy!
IMPORTANT: You must have the center detent ball removed from your t-case. If you already have that removed then there is no need to fully disassemble your t-case, but if your case still has it in place you must split the t-case to remove it. There are instructions for this elsewhere on here so I will not cover this.
Here is the reason I had to dive into my t-case, on a recent wheeling trip my driveshaft was crimped into the extended position and the stress from driving it out of the rocks caused the front output shaft to shear.
I also had some bearing noise I wanted to investigate as well.
To get started, remove the stock shifter and set it aside.
Next remove the front output housing from the t-case. There is no need to remove the front flange. I do however recommend draining the gear oil prior to this step or you will have a big mes on your hands (and everywhere else!)
Now clean everything up so you can actually see what you are working with.
You should have something like this, but with the flange on it.
Next you need to drill a hole for the new shift linkage centering bolt.
First drill it 13/64 or a #7 so it is the proper size for 1/4 20 tap. (double check my bit sizes, they may be wrong)
Line up the center of the hole on the casting line in the shift tower, and on plane with the stock shifter locating tabs.
Carefully drill through both sides of the shift tower. making sure everything is square and lined up. (again use the casting lines as a reference point)
After drilling through both sides, use a 1/4" bit to open up the first side only, and then double check that your tap will slide all the way through, you man have to open the hole up one additional size to clear the tap.
Carefully tape the far side of the hole. Use care because it is aluminum and it is thin where it is being threaded.
Now it is time to start making pieces and parts.
Out of 1/4 steel make 2 pieces that mimic the end of the stock shifter as shown in the pictures below. the "ball" area needs to be smaller than the stock ball to clear the locating pins in the shift tower. Make the top long enough to attach some type of shift lever to later.
I'm sorry that I don't have a pattern to post or even a better image, but you should be able to get the idea.
You also need to make a couple of spacers, I used aluminum, due to the fact that it was easy to work with and it was on hand. you can see the overall thickness in the picture below, and the outside needs to be radiused to fit inside the shift tower.
You also will need some nylon washers from the hardware store, I think mine came from Home Depot. They are approx 3/4" diameter, and .060 thick. I used 4 one between each spacer and the shift arm, and 2 between the arms.
To ease assembly I made a slight modification to my original design (I wish I had [idea] sooner) I drilled the center holes of my shifter out large enough to accommodate a sleeve that fits through everthing, and holds it together as one piece. It makes Assembly MUCH easier.
Oh, the piece I used was a Bick pen, just cut a piece small enough to fit inside the shift tower.
Here is everything assembled and ready to go together.
:-[Please note that from this photo on I assembaled things incorectly. If you look at the arms in the pictures you can see that the top arm has been clearenced slightly. That is suposed to be towards the t-case, not away from it.
After I assembaled everthing I realized that it wasn't fully engaging in low range and that my shift levers were pointing the wrong way so I hade to bull the shifters out and rearange the pieces. DOH!
Here is what it should look like installed in the housing (note, the output housing can not be put on the case with the shifters installed)
If you look closely at the above pic you will see where the shifter arm needs to be clearanced to have enough room.
Here is a shot from the frontside where you can see the new 1/4" bolt running through the shift tower.
Everything reassembled. This is where I realized that I screwed up and had my shifters wrong. It is slightly confusing to me because I have changed them 3 different times since my original installation, sometimes with a torch and sometimes with a welder.
I would reccomend that you incorporate into your design the means to bolt the shift handles onto the new shift rods. I originally planned to do this but got to excited to try it out and just welded on two pieces of rod. It hasn't bugged me enough to change it yet.
I also reused the stock shifter boot without any modifications, and I filled the area below the boot with grease to help keep the water and dirt out, it works OK, but is not perfect. There is a vendor on here who is supposedly working on a boot for a twin stick shifter, but I haven't been able to get
Feel free to ask any questions you have,
)
