2003 Tacoma DualShift Twin-Sticks Installation

Hello All,

Today I'm discussing the installation of the Twin Sticks from The Driver's Market (www.thedriversmarket.com). The product is known as the DualShift and the model number we're installing is the DS-01. We'll be installing these on a VF2 transfer case in a 2003 Toyota Tacoma with the A340F automatic transmission. The "arms" of the DualShift can be reversed to also be installed on a VF2 transfer case on an R150F manual transmission. This should act as a general installation guide for all 1st-gen Tacomas and all 3rd-gen 4Runners. T100s and V6-1st-gen Tundras can follow along with minimal adjustment.



For this installation you'll need a drain pan for t-case oil, a socket kit for removing the driveshafts from the transfer case and disassembling the transfer case, a punch and a hammer for removing/installing a roll-pin, a pry-bar to separate the case halves, RTV/FIPG (high temp) for resealing the case halves, gear oil (I like the Royal Purple 75w90), an output flange nut, a phillips screwdriver for removing the shifter bezel trim, and a customized shift boot (2 factory boots in your trim color that you've stitched together). Optional - a double rubber boot.

Part 1 - Removing the transfer case

1. Block off a front tire so the vehicle cannot roll, pull E-brake to lock up rear axle.
2. Inside the cab start by unscrewing transfer case shift knob. Unscrew the plastic shifter bezel (with leather boot) from the center console and from the transmission hump. Depending on vehicle, you may need to unbolt/unscrew the center console and tilt it back to have enough clearance to remove the plastic shifter bezel. This is the case for my Tacoma, so I've unbolted, 10mm, my center console and leaned it back. Once the plastic shifter bezel is removed, set it aside.
3. Unclip any plugs that are found on the metal "support" bezel. On my Tacoma there were 2 plugs. Unbolt the metal "support" bezel from the transmission hump. These are a series of 10mm bolts on the automatic, and phillips screws on the manual. Once unbolted, head under the vehicle.
4. From under the vehicle, unbolt the driveshafts from the t-case output flanges, 12mm, and unpin the linkage from the transmission shifter to the transmission. If you accidentally shift the transmission shift lever in the process of removing the pin, that is OK since the vehicle is blocked. Return shift lever on side of transmission to park position. Go back into the cab.
5. Now that the transmission shifter linkage is unpinned, pull up and slightly rotate the metal "support" bezel clockwise and pivot out of the way to provide access to the transfer case shifter. This will take some finesse.
6. Once access is provided, unbolt the transfer case shifter, 12mm, and remove it from the vehicle. Head under the vehicle.
7. Unplug the transfer case plugs, there should be 3-5 plugs depending on year and vehicle. My transfer case had 3 on top for the shift rail positions and 1 on the rear for the speedometer.
8. Unbolt the transfer case from the transmission, 12-14mm, and SAFELY remove it from the vehicle. I was able to do this alone by setting it on my chest and rolling it onto some plywood and sliding it out from the vehicle. If you have a friend and/or a transmission jack, use them.
9. The transfer case has now been removed.

Part 2 - Unlocking the transfer case

1. Drain the transfer case of oil. You don't necessarily have to do this from the drain plug area, I left mine upside down overnight to let it drain from the shifter opening.
2. Remove the accessories from the t-case, this includes the vibration damper and the plugs from the shift rail housing.
   
3. Unbolt the front driveshaft flange nut, discard as you will not be reusing this. Source a correct nut for your transfer case for reassembly. My part number was 90179-22016. Once unbolted, slide off the front driveshaft flange from the output shaft. Set aside for now.
4. Using an allen key, 6mm, remove the plugs from the either side of the case and remove the springs and detent balls. Set them aside for now.
5. Unbolt, 14mm, case 2 from case 3 (down the middle of the transfer case). They will be held together with sealant. Carefully and slowly pry the case halves apart. Take note to pry near where the dowel pins are located, this is likely where the case will get stuck.
6. Once the case halves are split, locate the reduction gear shift lever (on the "drivers"/left side of the transfer case). Using a small punch and hammer, punch out the roll-pin that keeps the shift fork on the shift rail.
7. Slide the shift rail slightly forward and tap the case until the "pill" slides out from where you removed the springs and detent balls. This "pill" is a locking pin and can be discarded as we will not be reinstalling it.
8. Slide the rail completely out of the transfer case.
9. Using an angle grinder or a dremel, cut off the over-travel "tab" on the shift lever and clean/smooth up the cut. It should look like the factory cut it.
10. Reinstall the shift rail through the shift fork and into the case. Carefully tap the roll-pin back into the shift fork to pin it in place.
11. Using a razor blade and brake parts cleaner, clean off all of the old sealant from between the case halves. They should be shiny if done correctly. Do the same for the shifter opening on the top of the case.
12. Apply a 2mm wide bead of RTV/FIPG (high temp) around the perimeter of one of the case halves, running a bead on both sides of the bolt holes.
13. Carefully push the case halves back together, taking care to make sure the split-bearing has not moved (you'll know what I mean) and that both of the shift rails are lined up properly in the front case as well. This will align the dowel pins and the case halves will seal.
14. Bolt the case halves back together, 14mm, and follow the torque specs for your vehicles VF2. Mine was 34 ft/lbs.
15. Once bolted back together, ignore this case for 24 hours to let the RTV/FIPG cure.
16. Reinstall the ball detents, springs, and plugs. I just went 1/8 turn past "tight" since there is no torque spec that I could find. There is also no factory thread locker or sealant on these ball detent and spring plugs.
17. Slide the front driveshaft output flange back onto the output shaft and install NEW bolt. Follow your vehicles torque spec, more important since it has preload. I used 3 ugga-duggas from my impact. Once on, peen in place with a punch.
18. Reinstall the vibration damper and the plugs from the shift rail housing.
19. Fill differential with oil (can be done later but easy to do now).

Part 3 - Reinstalling the transfer case

1. Under the vehicle, align the transfer case onto the transmission and bolt it on. Replug all plugs. Go into the cab.
2. Lay a bead of RTV/FIPG around the perimeter of the shifter opening. Install the DualShift, with the "arms" oriented to the left (AUTO). Use factory 12mm bolts to tighten down DualShift onto transfer case. Take care not to over tighten as these are steel bolts going into aluminum threads.
3. Cut a slit in the factory rubber transfer case boot and reposition the metal "support" bezel while sliding the boot over the shifter "arms", one through the new cut and one through the factory opening.
4. Bolt down the metal "support" bezel and plug in the factory plugs. Go under the vehicle.
5. Once under the vehicle, repin the linkage for the transmission shifter to the transmission. Go back to the cab.
6. Remove the shift boot from the plastic shifter bezel. Install your customized shift boot (2 factory boots in your trim color that you've stitched together) onto the shifter bezel. Reinstall the shifter bezel and center console.
7. Shift the transfer case into and out of all the gears. 3 gears on the left shifter (L-N-H) and 2 gears on the right shifter (2x-4x). Check each gear combination is corking on the transfer case's output shafts. Make sure that the shift boots are not pinched anywhere. If all is done and working correctly, install the shift knobs and head under the vehicle.
8. Reinstall driveshafts.
9. Congratulations, you now have access to new gears, 2N and 2L. Gears that are not readily available from Toyota!

More information can be found by watching the installation video found here https://www.youtube.com/watch?v=P3b586-iVI0&t=1656s

 

So this basically adds 2Lo mechanically to ADD actuated models?

 

Ouch.

As a consumer, my question will be, what is the difference between thedriver brand compared to front range or Rad because the price point is much higher.

 

Adds 2wd-L to J-pattern case by removing the “pill” and allowing each shift rail to be control independently through their own shifter. Will not work with ADD push button H/L case.

 

Guess I am confused because I've had 2Lo simply by not locking the front hubs and putting in 4Lo. I have a zombie setup of a j-shift and ADD, but I would assume manually locking hubs work the same way

 

essentially the same thing. Only difference is the twin stick will prevent the tcase from spinning the front shaft vs unlocking the front hub as you stated

 

Yes that's correct, this adds both 2LO and 2N

 

I designed these because I had previously looked at other brands shifters and I was not satisfied with 2 factors: 1) How they look in the cab. 2) How easy they are to service. The TDM shifters are an out of the box solution that do not need to be modified to fit your cab. They are offset oriented to work in the left configuration for the A340F and in the right configuration for the R150F. There is no bending required and the handles are black anodized. They are also built around a central fulcrum so the whole assembly is held together with a singular bolt. The shift keys are a hardened steel whereas the housing and the shift handles are 6061 alum. Each handle is sealed with an O-ring. This keeps the unit simple, sealed, and strong.

 

Regarding cost, we are an extremely small team - 4 people. We manage everything from the design to the shipping and everything in between. Prototyping is extremely expensive.

This is correct

 

@accountant_mechanic_

You plan on making a tcase ebrake setup, similar to the RF1A? I’ll be interested. At one point, it was available for the VF2 but production stopped.

 

I am certainly not opposed to designing a VF2 E-brake setup, but as of right now we do not have the bandwidth as we are deep into designing manual actuators for front differentials both to replace the air box and the electric box. I want to get away from VSV setups on 4Runners and Tacomas if I can.

 

true. a preformed stick saves a lot of time. If I hadn’t done the FROR, I wouldn’t mind trying yours out. I’ll keep it in mind and referred to it when people ask

 

Last night the first 3rd Gen 4Runner (2002) received a DualShift following these instructions.