Does anybody know where there is a detailed write up on removing the ADD system and permanently engaging it on a 2nd gen?

 

Are you serious?? Why in the heck would you want to do that? Please explain.

 

Is this so you can put on manual-lock hubs and not have the differential disconnect thingy? I'm not sure if that works to permanently engage the ADD anyhow...

 

You can install manual hubs and keep the ADD. Then you can have both - lock the hubs before hand and drive with ADD unlocked, then put it in 4WD whenever you want. Great in winter.

There is a writeup somewhere about removing the ADD servo, but not the axle disconnect mechanism. Personally I don't see much value in doing that, the ADD mechanisms aren't prone to breakage.

But if you want to remove the ADD properly, you'll need to get a driver side axle tube and axle from a non-ADD rig. If you remove the solenoids you may have to do something with the wiring to get the 4wd light to work.
(edit) Looks like you just connect the two wires together at the axle and the light will work fine. Nothing else should need done with the wiring.

 

you've got to get that oil seal from a non add rig too

 

There is a writeup but you eith have to search for manual hub conversion. I can't remember the site. What i did when I converted to manual hubs was run the vacuum line that locks the ADD straight to the check valve that goes to the intake. Just bypass the vsv for the ADD and cap the "unlock" hose off. This is the quick way. Another way is to go into the ADD actuator and permanantly lock it.
One hose is red the other is blue (clean them to see the colors). After you do this yo can remove the canister on the passenger wheel well and the VSV for the ADD. Only do this for manual hubs. I did this because my VSV went out and I didn't want to replace them.

 

I took the ADD actuator apart and inspected it, and looked at how it and the axles work. I see no reason to disconnect or remove it. I just added manual hubs and all is good.

 

This is one option:
- http://www.4x4wire.com/toyota/tech/add/

Or replace all the ADD parts with similar parts from a non-ADD truck. You can also use manual hubs and keep ADD. Unlock the hubs and you keep the front axles from turning. Lock the hubs and you can have normal ADD operation.

 

About three or four years ago I did it to a 90 4Runner.. as per the above link I did the hose clamp to hold the shift fork in place.. manual hubs and it worked great!!

 

because the 4wd mechinism is currently "switched" via vacume. loose a vacume line on the trail, and 1) the motor is going run like crap and 2) you might find yourself without 4wd. and who wants to f with vacume lines covered in mud/snow etc.

occam's razor or KISS.

the fewer parts the more reliable the system.

 

That is exactly why I want to do it. I do have manual hubs also.

 

I have a non ADD tube 4sale

 

i did the manual locking hub swap last summer and have wheeled in all sorts of terrain. i have not experienced any difficulties with the system what so ever. i had planned on removing all the add system but figured i would give it a try first. i have a copy of the removal write-up in the glove box and the necessary tools and parts in the back ready to go if the current set-up fails. others have wheeled longer than me and have had no issues to date, i see no need/reason to remove it.

my 0.02.

lee

 

So,,, if anyone is still there.

The parts needed to remove the ADD system completely is an axle tube and axle from a non ADD front end, and an inboard oil seal. The rest is just removing and capping vaccum lines and canisters? Is there anything connected to the ADD vacuum system that would be disabled when you remove all the vacuum parts from the ADD?
Thanks

 

I don't think anything else is connected to the ADD vacuum system.