Fo-runna

So, was reading up on inchworms lefty gearbox and something in there got me thinking... is it possible to manually wire up the ADD to a toggle so you could essentially have 2wd-low??? Kinda like an ADD equivalent to the grey wire mod. As it is, the ADD activates when 4wd is engaged so seems like some wire and a switch you could disable that?!
I put my boat in on a very steep slip and it's either work the clutch or 4-low on pavement... neither an attractive option.

DavidAlexander

That is an interesting idea. I want to see what some of the really knowledgable guys think.

toyota4x4907

going like 10-15 feet in 4wd on pavement at very slow speeds won't hurt.

if you want 2lo, get some manual hubs and just dont lock them but put it into 4lo
Or can you not put manual hubs on 3rd gen 4runners?

littlecommando

X2, dont see why you would need it

eric-the-red

Should be possible, the ADD is probably controlled by a switch in the transfer case that tells the ecu that 4wd has been engaged. Just put a switch in the circuit for that switch so you can select 4wd without letting the ecu know. On my 2001 that switch has red/black and white/black wires, but 2001s are a bit different from the earlier 3rd gens so yours may not have those colours.

mastacox

There's no reason why it wouldn't be possible, I've thought about doing the same thing. All you would have to do is find the wire that actuates the ADD vacuum valve, and tap a switch in-line with it.

crolison

Ding Ding Ding Ding Ding, we got a winner here.

Easiest way, there is a switch in your tcase on the right side with wires coming out of it, you can put a switch in between those wires to break the connection. Which will give make the 4wd computer think your in 2wd.

Fo-runna

It's like 75 yards or more from water to flat ground... and it's steep. Plus it could be fun to screw around in locked 2-low. I do like the idea of manual hubs so I'm not pushing the front axles on the highway but it's so sweet not having to get out an lock em' like I had to on my old yotas.
So, is the circuit closed with those two wires when in 4wd or opened??
ABS on/off would be sweet too.

crolison

when the switch is closed it is in 4wd.

Adam F

You WANT 4wd on a boat ramp. Helps tremendously in traction, ESPECIALLY when your rear tires are in the water.

4wd on the pavement going STRAIGHT is 100% perfectly fine for the truck. Its only when you make a sharp turn that you start binding the drivetrain.

So going up or down a nice straight boat ramp poses NO problems to the 4wd system. When you get to the top, just put it in 2wd and go about your business.

Only time I can see a problem in 4lo is going DOWN the ramp, where you might have to manuever the boat, in which case 4wd is really not needed.

And if you get manual hubs, you can still have on the fly 4wd shifting. Just keep them locked. It acts the EXACT same way as if you had stock hubs.

But if you still want a switch, just find the power to the solenoid and switch it. There is a writeup here about Limited models with the pushbutton 4wd to do this very mod. (no switch, just defeats the system automatically going into 4wd when shifted into 4lo)

You can just pull the fuse with ABS. Or wire a switch inline with the fused output.

And maybe you could even pull a fuse for the 4wd? I dont know if there even is a fuse, but its worth a shot.

jdsdj98

No, No, NO! That's not the exact same as stock hubs at all. With the hubs locked, the truck's motion spins the entire front drivetrain. The only disconnect in the entire drivetrain in that scenario is inside the T-case. What this means is unnecessary wear and tear on your entire front drivetrain. I nearly ruined a front differential and completely destroyed a T-case doing this. Before I knew better, I used to lock my manual hubs in October and then unlock them sometime in April, all so I could have on-the-fly 4WD shifting during the winter. If I'd only known then what I know now. DO NOT do this. I speak from experience.

[edit] Let me expand just a bit - Don't do this for any extended period of time or distance. Driving short distances is probably fine. Just don't do it for thousands and thousands of miles like I did. If you're driving with the front hubs locked in 2WD, always be aware of the unnecessary wear and tear you're putting on your vehicle, and unlock them at the first possible opportunity.

I'm a Tacoma guy, so I don't know which Runners have push button 4WD, but if you engage 4WD via a shifter, check out the twin stick mod. That's true independent control of 4WD selection and hi - lo selection. And someone please correct me if this mod doesn't work for his truck. I'll delete this if so.

mastacox

It's the same as stock drive flanges on 2nd and 3rd gens with ADD (although the 3rd gens are much more difficult to convert). Stock, a 4Runner with ADD has most of its front driveline components spin in 2WD, and the differential's long-side shaft has a sliding sleeve on it that disengages it. If you put on manual hubs but keep the ADD system, leaving the hubs locked spins the same components as would have already been rotating.

jdsdj98

Thanks for the explanation. Any time I hear someone talk about driving in 2WD with manual hubs locked, I picture all the mess I made under my truck. Sounds like ADD puts a different "spin" on that, so to speak.

Maj

You might want to exercise a bit of caution if you do this mod. In low range, the engine torque multiplication is quite extreme. I had an old IH Scout that I was wheelin' in low range without locking the hubs (I just needed more torque, not traction). I was climbing a steep hill and decided to floor it just to play around with some wheelspin. An enormous "bang" resulted and all forward motion ceased. When I looked underneath the rig the driveshaft was twisted in half - just like twisting and ripping a beer can in half.

yotaconvert

did you ever figure out the toggle for the add seems people like to get off topic i did an auto to manual swap and i dont have the luxury of putting a switch on my transfercase wires so any help would be great

crolison

run a momentary spdt switch with power to it to your vaccum solenoids on the drivers side fender well. So one way on the switch will lock the add, and the other way will unlock it.

Its what im running on my runner.

Blkvoodoo

why not just pull the 4WD fuse in the dash ? or wire a switch before/after fuse to kill the circuit ? won't energize the vacuum solenoids, and you don't engage the front drive collar.

As for the need, horsing my trailers around thru my gate and around the shed, slipping the clutch is eliminated ( it's a tight turn ) and the speed is much more controlled.

hross14

I like this idea also--having low range--especially nice for towing and it let you stretch your gears out

Gerdo

Can you flip from 2wd and 4wd on the fly?

crolison

i can, if i lock the the add first then flip to 4wd, but I have a front locker which keeps everything spinning the same speed. Im not sure if you can on a normal truck.