LS1Steve

I swapped a JDM 5sp tranny/tcase (had to, budget...), which is a stock 4runner tranny but from Japan-sold trucks.

Rather than the J-pattern tcase which lets you shift in and out of 4wd, this one has a 3 position linear pattern, low gear, neutral, and high gear. It is always in 4wd out of the tcase (always spinning the front driveshaft in addition to rear) and just used a push-button for actually engaging 4wd by locking the ADD.

The electricals are all different, so I have nothing connected to this tranny electrically, so i'm currently trying to figure out to install a toggle switch to manually engage the ADD. But instead of doing that...would there be any problem with permanently engaging the ADD and just using the manual hubs for 4wd? I know I won't have shift-on-fly capability, but if I can't figure out how to manually switch this ADD on, I don't have a choice.

I was given tips in another thread on a relay for the ADD under the dash "above the throttle pedal" but can't seem to find that under there, maybe because the person who mentioned it had an auto not a 5sp .

DeathCougar

iTrader: (23)

You can run a switch to the ADD VSV's under the hood i would think.

Btw, how much money did you save vs. a used one that you are spending this much time, money, and hassle to make this jap crate trans work? this is one of the big reasons I always preach against using Jap crate parts.

LS1Steve

Got a mint tranny & tcase w 40k mi for 600 shipped. I think it's a decent deal compared to the domestic stuff I saw. A lot of people talk bad about the JDM's, but it's the same toyota stuff quality-wise. I have to customize a bit, but its a 230k mi truck so there's already plenty of repairs/customizations everywhere.

I don't want to turn this into a debate on that....so back to ADD....can I run in full 4wd (add locked) and just unlock hubs? i figure, the diff is always spinning anyways as well as the axles... the axles would just spin now off the diff rather than by the wheels

I was planning on just switching the vsv tubes, swapping the engage and disengage (so that it's always engaged rather than disengaged).

mt_goat

I can't think of any reason it wouldn't work, as long as you unlock your manual hubs when you don't want to be in 4wd. The ADD just locks the drivers side cv to the drive line. The passenger side is always locked anyway and the normal factory ADD hubs are always locked. By unlocking your manual hubs you'd be disconnecting both wheels from the drive line which is even better than what the ADD does. I guess the drawback will be both CVs will always be spinning even with the hubs unlocked.

Flash319

You could bypass the VSV and just run a vacuum line to the actuator on the diff so that when the engine is running the vacuum is pulling the ADD in. If you want to switch it just run a switch to the vacuum valve (VSV) and supply 12V. With that case there is no point to having manual hubs as it is not saving anything. $600 is a lot for that IMHO. I have gone through 2 5speeds and I have paid $150 for a used trans and the transfer case is thrown in for free because they never brake (4 cyl gear ones).

82yota

Why is it always in 4wd? I've got a JDM transfer case and tranny on my turbo diesel I got from Japan and there is an electric motor on the back of the Tcase and engages the 4wd. I have not figured out how to get the ADD to work with mine yet. Mine has the same shift pattern as yours does. H-N-L but mine has a button on the side to engage the 4wd. You sure your tcase doesn't have a motor on the back of it? I just tricked the front ADD to run all the time and tricked a few of the wires to let me shift in and out of 4wd when I want to. Mine seems to work ok but sometimes the 4wd light beeps and blinks at me but that is a poor connection in the front end I'm quite sure. Did you swap it out because of the tranny not working or the transfer case not working? If it was the tranny you could probably put your tcase back on and be done with it. I may do this if I get tired of this electric one.

LS1Steve

mine does have that motor, not sure how to make it work since i have no connector to put into it. sent you a pm.