The point of manual locking hubs is to lock in the ADD system. So when you select 4wd nothing happens until you get out and lock the hubs.

 

Hi, another newby here; I haven't found the specific info yet, and my Haynes doesn't have detailed info. perhaps someone can direct me to the right spot or give specific instructions for a '91 4runr V6/5 speed with ADD.
Problem: front hubs not engaging, no indicatir light on dash. So far I've found a wire connector on the t-case switch that i suspect is NG.
Questions: how to test switch on t case? How to test switch and actuator on front diff? Thanks.
Jim

 

Haynes is useless.

The manual is posted on the internet, nctora.com I think. Toyotas switch grounds rather than the hot side.. usally. ADD is problematic. Most people just put on manual hubs, Warn or Asisn and lock the ADD in.

 

I've read conflicting post's regarding the conversion; some say you do just the hubs and some say you gotta do the axles, CV's, etc. I could probly do the hubs only but not the big 'ole repair.

 

Why not jump in?

Pull the hubs you have and look. Not like you need them today. Look at the ADD actuator and see how it operates. Then you will have a better idea about the conversion.

 

ADD front hubs are engaged all of the time. If your spinning the tires and the CV's aren't turning there is a major issue with either the CV splines or the drive flange is shot.

 

You can do any level of the swap you like, this is whey there are people that saw one thing and other say something else, because there is not one answer.

Simply replace the ADD drive flanges with locking hubs and with hubs locked, you have exactly the same setup as you do now, i.e. locked hubs = drive flanges. Unlock the hubs and you stop all the CVs from spinning.

Or to eliminate the ADD, run constant vacuum to the actuator engage fitting, or open it up and lock it in place with a hose clamp or remove it and replace with a non-ADD center section.

Your choice, depends on how much work you want to do and how reliable/strong a final result you want to achieve. And you can do it in stages, swap in the hubs and if that works for you, you are done. If not, run the constant vacuum line, if that does not work like you want, clamp the actuator and if that fails, swap for a non-ADD axle. And of course there is the ultimate ADD-delete of SAS

 

Hi All,
Got my ADD repaired, no vac to the switches and one of the wire plugs from t-case repaired. Thanks for the helpful words, looking forward to getting more things done in the coming weeks! (Like the "small" fire I had a couple weeks ago when the pos lead from batt to starter grounded because the insulation had melted because it was sitting on the exhaust manifold.....)

 

that's it I can't set it up the way I wanted it!!!!! I guess it's time for SAS jk

 

I'm Fairly New here, and just wanted to say Thnk You to all who are contributing to this site!

Lots of VERY usefull info on here!

Keep up the good work!

The Menace

 

I read Wabbits comment about too much grease causing suction which makes the hubs hard to turn-that explains why the hubs on my 1991 were so tight-when pulled the dial off the whole thing was filled with grease. So a light coating on all parts is sufficient? What about the type of grease? I had Warn hubs on my FJ-40 way back when and in the warmer months you could almost turn them with one finger. In the dead of winter (below 20 degrees) the grease got stiff as all hell and I would use a set of channel locks to turn them. What should I use when I refurbish mine?

 

I used mobil synthetic grease. A light coating on the gaskets and I can easily turn them when it's 10 degrees out.
Most peeps apply too much grease and it causes problems.

 

Removed

 

You are correct sir.

 

Just curious what the point of having the gold washer and bolt installed is once you've switched to the manual hub?
Searched but couldn't find much on that specifically.

 

The gold makes it look cool and add an extra 3.5 hp Haha jk

 

I'm running stock hubs on my '01 Taco, and I'm not planning on changing to manual. I was wondering if I have to worry about mud getting in the hubs or dirt, whathaveyou. And also if anyone could give me tips on a good way to do a thorough clean on my truck after going on trails that'd be great Don't want all that mud and dirt grinding down my parts!

 

Holds CV in place or a C clip. Seen both too.

You don't have any hubs to service then.

 

So I don't need to worry bout getting mud in my auto-locking hubs?

 

You have ADD not auto locking hubs

:wabbit2: