FJ Cruiser T-Case Install in 2007 Tacoma 6-Speed Manual

\/\/\/ He's the pro and he's right!

But to let you know my experience...

From reading through Wyatt's forum what you are calling the "Outer Gear" is the "Input Spline". In our Manual transmission trucks, our Transfer cases have a beefy 23 tooth "Spline" that in direct contact with our transmission... In Automatic transmission trucks, the transfer case has a 22 tooth "Spline" that actually connects to the transmission through what looks like a geared coupler to allow transfer to the transmission.

So when looking at the "Input spline" there is 5 bolts holding on a cover that protects it from the elements. That cover and the gear set are the only 2 things that you need to swap out between cases!

Also even though you say you don't need it.. Why not have it just in case... Do the twin stick mod while you're at it! I have a single stick in my truck right now and I went ahead and did the mod and it still shifts normally! It's completely safe!

Also for future reference, a HUGE TIP! Make sure both cases are in 2wd before splitting, and use VERY TOUGH POWER TOOLS!! Splitting cases with only a 2ft torque wrench and strength power by yourself is tough!

 

Updated!!!

 

I can appreciate the wisdom of what you are saying about twin sticks but I also am not the only driver and don't want my family members to have to take a course in how to drive it.
Still thinking about the ADD wiring and running a relay off of the TC switches. Will talk more after some thought about that. My stupid Haynes manual does not have a schematic for the 4wd system if you can believe that.

 

awesome write up brother lol that job would overwhelm me i would need a shop to tackle something like that for me..

 

That's true.. But The standard Reverse J shift pattern still applies with a single stick mounted on a modded case. Well I'm still trying to work out the bugs in my ADD.. This is the most annoying thing ever! So i'll let you guys know how that goes..

I appreciate it man! It really wasn't that overwhelming.. just time consuming. You just have to take your time and be patient also organized slightly! I knew that this has rarely been done on this sight so I thought I would add it.

I have all the thanks in the world owed to Wyatt from Rock Solid Toys! He is a life saver! If it wasn't for his sight I would still be 2wd... Or wasting money on a part that was just going to fail again and again!

 

Your not going to be able to run the ADD off of the TC switches unless you can find a relay the will turn on for a moment and then turn off and then do the reverse when you go out of 4wd. That is the reason there is a computer to run the 4wd system. You see, you need the ADD to be activated and locked before you go into 4wd in your transfer case. Especially if your trying to engage 4wd while still moving. (Shift on the Fly). If it's not engaged then your system up front wont be spinning and the moment you try to put it into 4wd while one system is spinning and the other is not...... Well, KaBoom!!! comes to mind real quick.

Just go with a DPDT momentary switch and stop giving yourself a headache. It'll save you in the end.

 

Hey Kyle. Your welcome man. It's the whole reason I started RockSolidToys.

 

Hey all, I posted this on RST as well; just trying to spread it around...


Ive been researching this with interest and thought I'd share and ask for feedback. Has anyone considered the following?
First regarding the twin stick: if you use the single stick and dont engage the ADD don't you still get 2wd low? Second I found that the FJ OEM used a siamese rubber inner boot that might work tidy neat and pretty (I can't post a pic from my I phone?). As well as a Siamese leather boot that seems a bigger base but might work? Seems to bring the TC shifter up right where I'd planned. I'm not sure how the leather boot is secured...yet. Lastly and more importantly it occured to me that it might be possible to move the 6 speed 4wd module from the FJ to the taco? I'd think that one might get lucky and the system similar and ADD same or compatable? How does the FJ 6speed system work and could it be transplanted for a more OEM finished product. Remember that I'm not the only driver so the added complexity for the family and risk of messing up the sequence is a big concern. Anyone have thoughts?
Thx SQ VFR

 

I love your dedication to this project. The shifter boots that you are referring to only come on the 6 speed FJ. The auto FJ does not have the Siamesed boot. Also, the computer for the FJ, or for that matter the Tacoma's as well will not work with this application in a Tacoma. The FJ system is too different and this swap requires that you disconnect the 4wd computer system all together.

 

So after reading all of this...what gains will I get over the stock tcase? I got the 2wd low part but other that what other options will I get? Since I have a SR5 with no locker would it be smarter for me to get a FJ TCase or get a rear locker?

 

Can't get both because I am poor but yes that would be awesome lol but I didn't think about 2lo being easier on the clutch which is great because I gave my clutch hell last weekend at UF haha and I did have problems engaging/disengaging 4wd which was very annoying

 

I haven't pulled a trailer with this truck but yes reversing up a hill requires way too much clutch for my liking lol

 

All of above ^^

If you had to choose between the 2 on which one to do first, I would choose the FJ Case! The reason for that is because the t-case actuator is sometimes a more troublesome part then the front ADD Actuator. You just have to make sure your breather is hooked up to the front ADD or you'll be in for one hell of a clean up and repair job! I'll post pics of that later..

When you do your locker (if you plan to go bigger tiers like me) then you might as well re-gear while you're at it. To finalize the reliability factor for most of your drive line, there are many options for the front.

But the problem with the front is it will probably cost you more then doing the T-case swap if you do it yourself!

Posted from : http://home.4x4wire.com/erik/diffs/#front
'03+ 4runner, '04+ Tacoma, FJ Cruiser, '05-07 Tundra, ?? Sequoia: 8" IFS diff.
- Driver's side
- Mid-pinion
- Clamshell housing
- 30 spline axles
- Carrier break: 3.91 and up, 3.73 and down.Posted by RockKrawler of Allpro Offroad 1-25-07
"The front differential is an 8" mid pinion IFS that uses a gear not available through the common aftermarket. It is the same as the Non-US Toyota Prado front differential. The only current ratios available are 4.56 from Toyota OEM Japan and 4.88 from Mossiero in Italy. All Pro has 4.56 OEM Toyota Gears in stock, and 4.88 on the way in.
Front install kits are also not available from the common aftermarket. It uses the rear 86-95 V6 pinion bearings, but everything else is unique to the FJ/Prado. All Pro has gathered the parts together and can assemble a kit for you by special order, and have preassembled kits in the works. No solid spacers are available for the front differential
One last thing - there is a case break on the front differential. This means there are 2 different cases, or differential offsets: one that fits 3.73 and down, and the other that fits 3.91 and up. So if you have an Automatic FJ with 3.73 gears and want to go to a 3.91, 4.56 or 4.88 ratio, you need an open diff from a stick shift wth the factory 3.91, or you can change to an aftermarket diff like an ARB and get yourself some extra traction at the same time.

The rear on the other hand is just like your standard ring and pinion setup!

All 2wd and 4wd T100's, '00-06 Tundra's, and ?? Sequoia's use a newer/stronger 8" 2-pinion diff. Tacoma 4x4's and Tacoma PreRunner's that don't come with the electric locker (aka "non-TRD), as well as V6 Tacoma 4x2's also came with this diff.
This diff commonly and mistakenly called an 8.4" or 8.25" diff, possibly to imply its extra strength. The ring gear actually measures 8". The extra strength of this diff comes from the bearing cap/truss and large diameter pinion gear shaft.
LSD's available is the TRD/Kazuma clutch-type 3-pinion LSD, the OEM 4-pinion Tundra TRD LSD, and the Detroit Trutrac.
Lockers available are the Powertrax "Lock-right," "No-Slip," ARB Air Locker, Detroit Softlocker.This diff cannot be fitted to an older style 8" axle because it uses a larger diameter mounting bolt pattern and because more space inside the housing necessary to accommodate the large bearing cap. The different bolt pattern also makes it very impractical to swap in an electric locking Toyota diff (the whole mounting flange would have to be re-done using a special jig).
- Carrier bearing truss and newer housing adds significant strength over V6 and 4cyl diffs
- Uses V6 carrier bearings, larger pinion bearings
- Uses shims for backlash adjustment instead of threaded adjusters
- Twelve 12mm Ring gear bolts
- 10mm axle housing studs with 14mm nuts
- 30 splilne axles
- 30 spline pinion
* 4Runners do NOT use this diff at all. Late-model 4Runners still use the V6 8" diff above.
** This diff is NOT swappable with V6, 4cyl, high-pinion, or electric locking diffs. This diff cannot be fitted to an older style 8" axle because it uses a larger diameter mounting bolt pattern and because more space inside the housing necessary to accommodate the large bearing cap.


So use the site above to get more info but the gearing and locking is where the money is if done right!!!

 

absolute wow!!! awesome write up.....might have to start saving my pennies for next year's big project!

 

OK well since no one is really talking about the FJ ECU much I've decided to just throw in for it. I've ordered a near new AT/TC from Edmonton for $700 and he's tossing in the FJ MT siamese boots inner and outer as well as the knobs for $75 the FJ AT TC ECU and harness plug will set me back another $150. So I'm still under the $1300 that the local dealer will charge for the actuator alone.

In my earlier post I mis-typed that I'd like to use the MT ECU when I should have said the AT. Funny thing though is the part number shows fitment for both the AT and MT but I cannot understand why as I don't think the MT FJ has an ADD on the front? curious.

I'm going to try to get the stick up inside, similar to the FJ MT. Now just for the fun of it for you twin stick guys, and for the benifit of moving my trailer(s) i see the merrit in 2WD low and hope to accomplish this with a dash switch (upside down?) so it's NC in the off pos and open in the on pos; lable it 2wdlow and have it interrupt the 4wd TC switch so the ECU doesn't know the TC went into 4wd and doesn't engage the ADD. The question is what OEM switch (appropriate icon) to hunt down for this purpose? Any one have any suggestions? I know I said I didn't want complexity for the other drivers in the house but I figure if this switch gets rocked there won't be any damage so no worries.

I wan't to get the parts on the deck and then maybe do this project in the spring or when i happen to get a few days off in a row so it might be a bit and I will post up a new thread and link this all together. Additionally I'm thinking that Wyatt and crew made this discovery recently and maybe word hasn't got out all that wide spread, especially locally, the FJ is reported as very tough so why would you need to buy one from the wreaker for your FJ = low demand, so I figure grab the parts sooner and avoid availability issues and price increases and worst case I can always sell it for Par later. For now I have reliable 4-Hi and no 4-lo at all, but good enough.

If I ever write this truck off I will have to buy it back to get all my mods back out of it! I never intended to mod the $hit out of it I swear. Meanwhile thanks to RST for finding the solution; I will copy this there to spread it around...

SqVFR

 

nice

 

subbed

 

It sounds like you're on the right track but in all reality you are eliminating the need for any kind of ECU.. So to purchase the FJ ECU would be pointless. If you follow the instructions on splicing and cutting then your interior lights will work and everything!

I've done the twin stick mod to the case and currently running a single factory stick. I have the standard reverse J shift pattern of the 2hi-4hi-N-4lo. You'll realize and understand A LOT more once you start cracking into the cases and see how everything is going to work. I had my doubts at first and then I talked to Wyatt and he helped me work out my issues and now I'm golden!

It's awesome that you have the factory boot and everything though. Do you know is he has an extra set of boots?

 

Yes but my concern is if one of the noobs in the family hits the ADD switch not knowing how to run the system and at best runs around On dry pavement with the front axel engaged or at worst engage it in such a way as to blow shit up.
As for the task itself I'm not concerned as I'm a mechanic for a living ( marine & HD) and with the RST write up and trail blazing I'm well prepared.

I'm just thinking that RST customers who are not hard core would appreciate a more OEM finished product. As for boots you be better buying them locally?

 

After looking at both the Tacoma and the FJ, to just swap in the FJ 4wd computer is not as simple as it would seem. There are a number of variables involved here. One being the year of the Tacoma and FJ you are using. You see, the 05 to 06 tacoma's, some of them did not have traction control like the FJ does. That system is integral with the FJ's 4wd system. Also, some had the atrac with and with out the rear locker and that would have to be addressed as well. There are many other small variables that would make this kinda of a pain to deal with.

Can it be done? Yep! Is it worth it to me to mess with? Depends on who the customer is and whether or not he/she wants it. I could make it work, but I woould need to find the correct year FJ computer for the application and if I didn't have the plugs I would need to rewire the pulgs on the Taco so the the computer would actually understand the information it was receiving. that would be a fun chore.