Bingo.

Or get a solid tube front diff(or lock the actuator over with a hose clamp), and get manual hubs. And delete the add system. No more 4wd problems.

That answer your question snowshredder?

That depends on YOUR definition of "better".


His truck has over 200,000 miles on it... And to my knowledge the relay has failed one time.

My guess is that $150 dealer, who knows salvage, relay will go another 200,000...

lol, I thought you were gonna say he installed a hand throttle!


God I love ppl that REALLY know how to fix things! :bang:

I understand what you're telling me here...But if the 4Runner came with it, I'd like it to work the way it's suppose to. I'd like to leave, locking the actuator in with a hose clamp, as a last resort. I know to some it might be a fix all that ends all, but that's not how I'd like to do it just yet. I'd like to trace the problem, and fix it. Now I did find this..

http://www.ncttora.com/fsm/1993/susp...26addcontr.pdf

But this is for the automatic transmission...if I'm incorrect, please correct me. And if it is only for the automatic transmission, can I get some help in finding the one for the manual transmission...I've been looking the last couple of days and haven't found it yet...maybe I need to spend more time looking still. Thanks for the help so far.

-Ted

Wow, you really wanted to keep ADD. :D

I opted for this solution 3-4 years ago http://www.4x4wire.com/toyota/tech/add/

Thank you...Far more instructive than what I've been able to find on here so far. Seeing as how this still retains the 4WD light on the dash with the proper operation of the 4WD system, I will now go this route...seems a whole lot simpler than tracing the whole problem and replacing what's broken...I also like how you can trace the wires back to the dash and eliminate some of the other non-essential items with in the engine bay. The other write up on here didn't delve into as much. Thanks again mt_goat..:great:

-Ted

So this is probably a stupid question and don't want to hi-jack the thread...

But is it ok to have the ADD system always engaged?

My vacuum hoses were jacked when I got the truck 91 Ext Cab PU SR5. (Still working through getting all of them worked out slowly) ..

So right now I have taken all the vsv's out of line and have a constant vacuum from the plenum to the 4x4 side. So I can still have shift on the fly..

And I have not (don't have the $$) changed to manual hubs.

So is this bad or will it cause a long term problem?

You can't afford $50? (estimated)

No friends with Toyota's? No pull-a-parts or salvage yards where you're from?

Man I love those old 4WD myths...

"front end" and "wear"...

Your question is: Can I drive around with my hubs locked all the time?

B/c that's what a locked ADD actuator with drive flanges is.

As for a direct answer, how bout you think about it?

(Sorry, just tired of spoon feeding)


PS. I put hubs on my T100, then pulled a vac on the engage side, kinked the line, blocked it and let go to fix my ADD actuator...

Worked every time as far as I know.

well, it's not GOOD.

but i honestly don't think it'll hurt it that bad....even with normal ADD everything up front is spinning anyway....

whenever i do my conversion and such i'm goin with manual hubs, simply for the MPG gain.

Thanks for the reply... I have only been connecting the 4X4 vacuum side when I know for sure I will be using it (inclement weather.) When its nice I
shift it back to 2 wheel... Just had to have a valve job/ heads milled and new
T-Belt and water pump done on it so funds have run out... Will still have to
do a muffler (just found a leak on the outlet side this a.m.) soon too...

Married with children ... so they come before the Truck.. :nopity:

The main difference with the functioning ADD is the ring and pinion, and subsequently the front DS is NOT spinning.


Any load on a GAS engine is bad. IMO they (the plenum's) are VARY sensitive and compensate by adding more gas to keep the correct air:fuel ratio.

Other than that... Short of a locker in the front I don't see much wear.

But use is wear, none the less.

OK I get the ring and pinion stuff... but I am confused about the vacuum from the plenum... that is constant suction regardless (right?) cause you
need vacuum for the 2 wheel side as well.

Not only that but from my understanding of the ADD system isn't the passenger side always connected anyway? and the vacuum for the 4x4 side locks the sleeve in for the driver side shaft.. and allows the 4x4 to engage?

Sorry I could be all wet here... (ie. wrong.... lol who me wrong ... ) yes it has happened before I have been wrong alot..

Yeah, that's fine.



Yes. Open diff law states: The path of least resistance.

Both shafts spin, but since the long-side shaft is disconnected, and there is resistance from the front DS and the R&P not wanting to spin that the short side spins the spiders inside the case.

And since it has to have a place to "come out" or "escape" (open/closed loop type thing) it spins the long shaft side stub shaft all the way up to the coupler, that in H2 should be un-coupled.

Couple the un-coupled coupler, and it's a regular old axle. But in order to have the connivance :roll: of not having to get out and lock the hubs, it's got that switch... That de-rails the coupler:D


This is basically THE SAME THING. only it's not, and it's from a Dodge.

http://www.4x4posi-lok.com/images/dodge_axle.gif

To all who thanked me,your welcome.
To all the haters....walk in my shoes. My Yota is a moving scrap yard. 240k and rotted to the core. Every turn of the key you can hear the theme song from Sanford & Son.
If you don't like how my valves look...don't look and keep the sarcasm to yourself or private. For some people,my solution could be their solution. Not everyone has the wallets that some of you have. Not all of us live in trailers so our Yota's are the best rig in the small town you live in. (bragging rights at the local Dairy Queen don't last long).
I do not go off road. I drive it to and from work in FEET of snow. I am not willing to sink large amounts of money into a rig that is dying just so YOU can be happy.
Do I criticize your efforts? No...so leave mine be.
Nope...not willing to salvage relays from yards after they've been in the weather for umpteen years,only later to have the same problem all over again. Nope,not willing to spend the money at the stealership so I can have bragging rights.
In short...
If you have nothing nice (or constructive) to say...then don't say it. Post your own thread. BTW....my solution has not failed. It works wonderfully. it's funny though....I read on hear about guys with lockers and solid axles,but yet at the same time. i read threads from the same guys trying to find solutions to their lockers and solid axles.
What color is your kettle? :)

If you dont want criticism, dont post on a world wide forum.

Even the nicest rigs get criticized. So its pretty obvious your "fix" will be too.

I agree. There is alot even I do to my own truck that I over criticize and would probably not do it that way on someone elses vehicle. But I have a bad habit, if it works and is safe, then why not. That's part of being original and practical with what works for YOU and NOT someone else. Everyone has a different way of doing things or how they think about certain solutions.

I wouldn't let it get to you that some people might question what you have done or how they would have done it. Instead of telling them to stay out of your thread etc etc, let them have their opinion. You know it works for you. That's all that counts. Besides, that lets someone else searching for info on the same issues on different ways that something can be done and why one way might be better or cheaper or whatever the reason may be.

:grouphug:

It's an open forum for discussion. If you didn't want to hear opinions on what you did and you're happy and it works just fine for you, then why post it?

I would think this would give you the option of locking and unlocking the front end independent of where the T-case lever is. So, if I were to install manual hubs and a front locker on an ADD frontend, and plumb in a vacuum switch like this, I could lock the manual hubs, and use the vacuum switch to lock and unlock the front axles from each other without getting out of the vehicle. Seems like it would be handy. But, I guess it doesn't fall into the list of "YotaTech Approved Mods"... (:

Why would you ever want to lock the front hubs and not be in 4wd? :hillbill:

You could accomplish the same thing with a properly operating vacuum switching valve along with a $3 switch and some wire from radio shack.

You really need that many options with your front end?