FJ case in a 3rd gen tacoma

CALLING HELP FROM OTHER CASE SWAPPERS:

I did the twin sticks because I couldn't find one with the stock single stick. Swap went fine but now when I drive, every so often the Hi/N/Lo lever pops into neutral from Hi. It's not on bumps either, it's at random times on smooth roads AND I even tried it with the center console out and it still popped out. Seemed like when I downshifted (manual transmission) it would want to pop but it's also popped when I went into neutral.. Any ideas??

 

I had the same problem.

Did you clearance the transmission enough for the shift rods to move freely? You can get extra weight detent springs, this did the trick for me.
https://www.yotamasters.com/shop/ot...products/heavy-duty-shift-detent-spring-bolt/

 

Yes I clearanced enough (that was my first issue when putting it back in) because big bumps on roads don't effect it at all, it's weirdly just when I downshift/go into neutral on smooth roads! I thought about the detent springs.. I'll try it out, thanks you the man!

 

Sounds like the exact thing I was getting, it only popped out of gear when there was no pressure on it (in between shifts, or coasting).

Detent spring should fix it!

 

Do you mind me asking how much of the shifter rods and transmission housing you grinded? If I pull back hard enough on the Hi/N/Lo stick, I can hit the transmission but I feel like I've gone as far as I can with the transmission and I don't want to go further on the shift rod because I'll break the oil seal. Trying to make sure it has enough clearance basically

Edit: just played around a little bit more.. seems it wants to pop into neutral when I engine brake in 2nd or 3rd gear. Is this the same issue you had?

 

I can't remember what the exact measurements were, but I basically ground the shift rods as much as I could without causing a leak. Then measured how far out the shift rods go, and just made sure I had room in the transmission with that jig.

Yeah that's what I had. It sounds like a stronger detent spring would fix your problem.

 

We should've measured, that was a rookie mistake, but I ordered the springs so I'll let you know. Thank you for your help

 

We all do it man, I just finished cutting the same piece three times for another project

 

You the man! Springs are in and it stopped popping into neutral! I was upwards of 4,000 rpms in 2nd gear and just cut out the throttle to just plain engine brake and I couldn't even feel it gripping to want to move, let alone actually pop out of Hi. They worked wonderfully!

 

That's awesome man, glad I could help!

 

Anyone else with a 3rd gen that did the FJ swap?. I would love you see what other solution are out there regarding the electronics, the ADD and rear locker. I went through the 2nd gen FJ swap forum but doesn't seem like their electronics pertains to us 3rd gens

 

I run an ADD wiring harness to a rocker switch inside the cab. So both ECU wiring harnesses are just dangling where they originally were but the front ADD is a manual switch I have in the cab. As for electronics for the locker, @BigWhiteTRD is your man to spoof the ECU

 

Is that wiring harness for the ADD something that can be purchase or is that something you made yourself? Either way, any link would be greatly appreciated

 

Check out the Instagram for further info (Tonya_Tacoma) but the link is https://12thstateoffroad.bigcartel.com/product/add-actuator-harness
It DOES NOT fix the dash lights (which means you won't be able to activate locker) but it makes it so you don't have to convert to manual locking hubs and you don't have to always have your front driveshaft rotating. Again, BigWhiteTRD would have more to say about how to get the locker to POSSIBLY work from https://www.tacomaworld.com/threads/4wd-ecu-spoofer-for-fj-transfer-case-install.693450/

 

The only dive (that produced significant results) into the electronics for the FJ swap (on a 3rd gen) that I am aware of is the link listed above by @Dkarr13
https://www.tacomaworld.com/threads/4wd-ecu-spoofer-for-fj-transfer-case-install.693450/

Note, I didnt set out to work on an FJ swap, but was asked to help out somebody who had done the swap but now had the dash lights. The solution I came up with is NOT what I would call 'elegant', and is more brute force. The solution provided in that thread consists solely of a SPOOF of the actuator signals and resistance for 2hi mode in the default position, and for 4lo when a cockpit switch is thrown.

This method removes the pesky dash lights in all normal operations. If you want to use any of the truck features that are available normally in 4lo, like MTS and ATRAC and Rear Locker (for the OR/Pro models), you have to shut off the truck, throw the spoofer to 4lo position, then start up the truck. After you do this, you should have full access to the modes your truck normally has in 4lo. And you can still operate your FJ transfer at will.

The reason this method requires the truck to be shut off, is that the 4wd ECU is expecting to see the truck's actuators sequence thru intermediate positions, and I could not easily spoof this sequence.

Somebody (not me) could use the info we have found to create a PLC or computerized solution that would be better, but thats not in my capabilities to do reliably.... and if its not 100% reliable, its not worth doing...

 

Forgive my ignorance, electronics are not my strong points. If I was to have my t-case actuator sitting on my passenger floor (Lol) and have a FJ case in place of the stock one, would I be able to turn the knob on the dash to 4wd/4Lo and trick the system that I'm in 4wd, while I use the manual shifter on the FJ case? That way the ADD and rear locker will continue to work "normally".... Or is the actuator there just to keep the dash from being lite up, but no longer functional

 

yes, that is one of the options (if you have both transfer case actuator and ADD actuator).

The drawback is that usually people do the FJ swap because their electronic actuators took a shT, and justify the swap partly vs the cost of a replacement actuators

 

BigWhiteTRD nailed it - problem with mine is that when I took the actuator apart, I messed up the timing in the gears inside the actuator. (You have to take apart the actuator to get it off the t-case). This is a problem, because now I can't just turn the knob into 4wd... Basically the actuator is there just so the truck doesn't freak out when nothing is plugged in.

So if you do end up doing the swap, could you do me a solid and take a picture of the inside of the actuator without messing up the timing?

 

I'll try my best not to mess it up, lol... I'll be sure to share the photos. Might be a couple months, I plan on doing this during the fall/winter

 

Good thread.......