etc.

I have been battling this for three weeks.

First off, my truck is a 97 T4R Limited w/ 4wd button.

I can engage 4wd (4H and 4L) instantly using the button, however, I can not disengage 4wd to go into 2wd unless I switch the vacuum lines on the VSV...

So far, I have:

* Visually checked all the vacuum lines.
* Removed and checked the neutral position and 4L position switch on the transfer case.
* Checked the TC actuator using an ohm meter. 185ohms. I tried to check #2/#3 and the body, but I couldnt get a reading.
* Replaced the ADD switch on the front diff.

Also, my propeller turns in 2wd.

Any help would be greatly appreciated

etc.

**update

I have 42.2 ohms at each of the VSV and the TC actuator engages and disengages when hot wired from the battery.

etc.

No body has any hints or wants to help????

What about the location of the 4x4 fuse?

bobby_duce

look at post 4 hope this helps alittle...

https://www.yotatech.com/forums/f16/...sengage-65516/

etc.

Thank you sir

I have tested most of the switches. 2 on the DS top of the TC, 1 on the TC actuator, and replaced the ADD on the front diff.

The switch on the top of the TC actuator gave a very low reading and I switched it out for the ADD front diff switch that I had removed. It didnt make any difference.

For some reason, the red VSV isnt switching off.

1993hiluxsr5

Hey, i had the exact same problem, i first thought that it was my vacumm lines but it turned out to be my t case motor, it sounded like it was turning perfectly, but in actual fact none of the gears were rotating therefore the actuator fork was stuck in 4wd :/ but try draining your tcase motor and poping open the gear cover and see if the gears move smoothly when you shift between 2wd and 4wd.
i also know a way to manually get it in 2wd so it can drive on the street.
hope this helps

etc.

pray tell

1993hiluxsr5

Okay I read earlier that you mentioned your vsv so I assume you have the stock add hubs yes. ? If so then I think I know how to fix it, your stuck in 4wd because one of your vsv's is getting a constant 12v supple Telly the add relay to stay in 4wd. This is most likely due to you t-case motor being stuck, it may sound as if it works but if there's a constant 12v on 1 of your vsv's when shifting between 4wd and 2wd then it's probly stuck.
To fix this you need to remove the motor of the t-case. Easily done with the 3 bolts on the back of it, when removed you should be able to pull it towards you About 1 inch and that's due to the selector fork. If it does not budge then your fork is stuck, if it does then it's your motor. Give it a quick service and test it on a 12v supply to ensure all the gears turn freely. If all is well and the motor functions correctly again reinstall and it should all be fix. Because after all it's the t-case motor that operates the vsv's.
Okay enough of that, to get it temporarily into 2wd you need to disconnect the vacuum hose off which ever vsv is causing the front hub to lock (I forget wich one blue or brown) then removed the 4wd sensor front the front of the actuator located under the front of the truck on the diff housing, inside you will see a tapers shaft that is all the way to the left, with a large flat screwdrive gently push it to the far right and it will be in 2wd again, if when the engine starts and it pops back to 4wd then you've Dixon edged the wrong vsv line , hole this helps. I have more info and some pictures if needed.

1993hiluxsr5

Sorry about all the spelling mistakes I'm on my iPhone and hit the wrong buttons Dixon edged is supposed to be disengage and hole is supposed to be help

etc.

WOW man. I want to thank you. Out of all the forums I've posted this, you are one of two people to take the time to really try and help

You are correct. I have add hubs and my red vsv is getting constant power. One issue you had not mentioned that I currently have, which may be a side-effect of the mentioned problems, is the blue VSV wont clear the lines when the power is cut. However, when I get the chance I will switch the new VSV with the old blue and replace the red where it was.

I can get it in 2wd, if I take the blue striped hose off the blue vsv.

Is there any oil to look out for when removing the actuator? I loosened it a little while back to remove it, but it seemed like it was wanting to push itself out. Not wanting to create another issue for myself, I tightened it back up. Any other tips for removal? Should the TC be placed in neutral?

Thanks again, mate

1993hiluxsr5

No worries I'm happy to help any way I can. I had this same problem and needed help myself.
Before you go blaming your vsv valves don't go cutting any wires just yet (I did what you were thinking) it might be as simple as the t-case motor, a quick easy way to tell is to unbolt the small gear cover cap on the side of the motor, this is a small rectangular shaped peice with a raised center circle, it's located on the left of the t-case (if looking from behind vehicle) take this off and be carefully of the small amount of oil that comes with it and just double check to see if they turn when shifting between 2wd And 4wd. Have a buddy shift with the engine off! While you look from underneath. If they turn then it's something either electrical or vacuum related but this was my culprit and I had all your symptoms exactly.
Hope you fix it man !

1993hiluxsr5

And another thing, sorry about double post but, of when you tired to take the t-case motor off and it started to pop out then that's a good thing as that's your selector fork spring, this means your selector fork isn't stuck . And don't worry it only moves about 1inch then stops. And on my truck there was only a few drips of oil.
To full remove the motor you need to get into that gear cover I was telling you about, inside you will see the actuator fork shaft and it's teeth, you need to remove the gears from inside there (very easy they practically fall in and out) then gently slide the motor off the shaft, then you can get into it,
WARNING OPEN UP THE BLACK CAP ONTOP OF THE MOTOR COIL SLOWLY AND CAREFULLY otherwise this might make the coil shoot outwards if it has wound up tension in it's spring. I took mine off and luckily it had no tension, if you turn it clockwise it tightens and stops and if you turn it counterclockwise it pushes itself out thus making the brushes pop around the shaft and a real bitch to reassemble

1993hiluxsr5

This is the gear cover with the gears and bolts to get it off highlighted
And the t-case motor

etc.

Well not really sure what the problem was, but I have narrowed it down and have by passed it.

My TC actuator was working as it should. When bypassing the VSV, my TC would engage and disengage depending on what side of the front diff actuator I gave vacuum. Awesome.

To keep things simple I gave constant vacuum to the blue-lined VSV vacuum line. This egages the front diff as if it was in 4wd. However, the TC isnt engaged till I press the button on the TC lever. I have instant 4wd drive when I want and it disengages instantly.

Not really sure what the main deal is, but I'm some what happy. I really wanted it to work like stock and not have the drag of the front DS constantly spinning, but all well.

Its now more reliable and it works.