Anyone an expert (or close) on the VF3AM T-case in Sequoia or 4Runner?

[redthies]

My Sequoia t-case is not shifting properly using the electronic shift. It is the multi mode case that gives you the AWD option. Apparently this case also came in ‘99-‘00 and possibly other year 4Runner Limiteds. It makes noise, the actuator rod moves, and lights go solid, but the case ends up in neutral. I can use the lever to manually shift from 2 Hi to 2 Low, but i need to get 4WD functioning. Since I have no forward or reverse gears once the e-shift completes, but I can shift back to 2WD and it drives fine. It seems like the actuator is not moving through it’s full travel.

I have been seeing people with clocking issues after taking their actuator apart, but i don’t think this is my issue as all have said they have a light show on the dash when it is out of sync.

Anyone have any experience with this issue?

Photo of the Sequoia since we all like those:

 

[bkg]

did you actually take the actuator apart? My understanding is that the only way to sync the actuator correctly is to split the case.

when I replaced the dual case adapter on the tacoma ~11 years ago, I pulled the actuator w/o research. After talking to a local toyota tech, I just did a junkyard swap.

Check out this thread on Irate4x4 - it sounds like it might be similar. https://irate4x4.com/threads/2002-4runner-wont-shift-into-4x4.390925/

 

[redthies]

Is “irate” the new Pirate?

There are two types of actuators for these cases. One does hi and low ranges, and mine does only AWD. Then CDL does 4hi lock, and mechanicAl shifter does hi lock to low lock.

 

[redthies]

So in that thread, the dash light was blinking because it wouldn’t complete the shift, whereas mine doesn’t blink, and it seems like the shift is complete, but it just leaves me in neutral.

 

[bkg]

So in that thread, the dash light was blinking because it wouldn’t complete the shift, whereas mine doesn’t blink, and it seems like the shift is complete, but it just leaves me in neutral.

if your shift is complete, it wouldn't leave you in neutral, no?

Did you remove the actuator at one point?

 

[redthies]

You are correct on the neutral thing, hence me saying “seems” complete. The dash lights indicate 4wd (AWD). I’m going to pull the cover and see what’s moving in the next week or so. Ideally, if I can gently pry the rod manually into the AWD position, I can just leave it that way, and engage CDL or low range as needed. Basically I’ll have a 100 series set up, which is great. I don’t think mileage will suffer too much more than a lifted V8 gets already.

 

[thezentree]

The actuator also controls the CDL, so if you try to engage or disengage it you'll be moving that shift rod.

Have you checked your tcase position switches for function? I'm curious about your dash lights showing it's fully in position when it's actually not. That's an uncommon issue, so I'd spend some more time troubleshooting before you pull the parts shotgun out of the closet. To repeat bkg's question, did you disassemble the actuator and potentially lose its timing?

If you determine it actually is your actuator, this might be helpful: https://www.toyota-4runner.org/3rd-...-4th-gen-t4r-2nd-gen-taco-actuator-works.html

 

[redthies]

I did not disassemble it. Every person that does seems to open a can of worms up. My first thought was to take the small cover off the small drive gear on the actuator and then see if it is moving when the 4x4 button is depressed. I don’t think I’ll take the other side apart at this point. My wife is away with our Tundra, so once she is back, I’ll dig into it a bit. We live in a small town in the mountains with no parts store etc, so I need a second vehicle here so I don’t get stranded if something goes wrong while troubleshooting. Driving the 15 miles to town on my tractor with chains and plow installed doesn’t appeal to me

I haven’t checked the switches for function yet either. From issues others have had, it seems to me more likely to be mechanical rather than electrical, but maybe I’m wrong?

I have not heard of anyone else having the same issue, which is exactly why I‘m asking for input from anyone who may have. Most every other person with a problem reports flashing lights on the dash, whereas mine move to where they are supposed to, (4 green lights), but I end up in a false neutral.

So the ”number 1 gear shift fork” moves part way to engage 4 high, and then moves further to engage the CDL and 4 high “lock”?

 

[redthies]

The actuator also controls the CDL, so if you try to engage or disengage it you'll be moving that shift rod.

Have you checked your tcase position switches for function? I'm curious about your dash lights showing it's fully in position when it's actually not. That's an uncommon issue.

If you determine it actually is your actuator, this might be helpful: https://www.toyota-4runner.org/3rd-...-4th-gen-t4r-2nd-gen-taco-actuator-works.html

Thanks for the link. Some good info in there. Do note, my rig is an ‘03 and apparently not the same as the ‘01-‘02.

The triangle cover (below with red arrow) is where the drive gear that moves the shift rod is, correct? It was my thought that I could just remove that cover and see if the gear is turning? And do you think I could manually move the rod to engage 4 high (AWD) and then close it up and leave it there?

I realize this isn’t an ideal fix, if it’s even possible, but it’s snowy here in the mountains and would really like to be able to get in and out of my driveway, and time is very precious these days…

 

[thezentree]

I wouldn't try to operate it without that cover in place, as I don't think there's anything retaining the pinion gear other than that cover. It's been a little while since I've had it apart though, so I could be wrong. That said, if the actuator is moving at all, even to the wrong position, it will be turning.

It'll be a fight to manually shift your transfer case, but I guess it's possible. You'll need to get all four wheels off the ground to do it and probably be turning driveshafts at the same time to get everything lined up. I don't know the correct position for AWD hi but i know it's out there somewhere. You'll want to pull the big plastic cover with the drive motor off the actuator and rotate that spur gear by hand to move the actuator, but BE CAREFUL - it is not really retained by anything either, and if it falls out and you lose your actuator timing, you're pretty much screwed.

I still think you should check your position switches before you start actuator surgery though. Reason being, if the actuator is moving and you're getting steady lights as if it's in the correct position, I doubt the actuator is bad. I'm thinking that you might have a bad switch that is telling the 4wd computer that the shift rod is somewhere it's not, or you have some kind of mechanical issue with the innards of the t case. I think a lot of the actuator issues people have are with corroded spiral contacts and the 4wd computer loses where the actuator is in between position switches (what my issue was).

All that said, if you're determined to mess with the actuator, you could start with just pulling the motor cover assy off and checking the spiral contacts for corrosion. It's not hard to do, just disconnect the electrical connector and pop the three screws out, but pay attention to what the cover does when you take the screws out - if it wants to torque immediately, there might be some pressure on the shift rod and if you pull the cover off at that point you might lose timing if the spur gear spins independently of the worm gear in the cover when that pressure is released. If you can turn it back by hand and it stays you're probably good, but don't take it off if it wants to fight you.

If you figure it out, please let us know what you find. Good luck.

 

[redthies]

Now I’m thoroughly confused.

I‘ll re-read your posts and the ones you linked when the time comes. I can’t get into my shop right now without 4x4, so it’s a Catch 22 until the weather here stabilizes.

I will for sure report back when I get it sorted out. The switch contacts are definitely a place to start, as the PO swears it worked fine just before I bought it, and I doubt he would lie as he wants me to get him a new career at the fire dept, so needs to stay on my good side!

 

[redthies]

Did you remove the actuator at one point?

So circling back to this… I managed to get the Sequoia into my shop today and got it up in the air. Tried shifting with it up and no pressure on driveline, but no joy. Same as when on the ground.

I did check all the external electrical connections and they are fine, but I noticed that all three of the bolt sleeves on the actuator cover were cracked, which leads me to believe someone has been in there before, and possibly jacked the timing. But, if they had screwed up the timing, it seems it would not drive in 2wd with lights showing it’s in 2wd, right? If the timing is all messed up to the point that it won’t shift, it wouldn’t (shouldn’t) be showing correctly in the 2wd position?

 

[redthies]

I found a service manager at a new dealer today, who has wrenched on these trucks. He was kind enough to do a bunch of research and emailed me a bunch of pages of the tech manual for my truck. I’ll revisit shifting procedures tomorrow and go through the 10 pages of troubleshooting. Hopefully it’s something simple.

 

[thezentree]

Good luck. I think I've exhausted the extent of my knowledge on these so I'm interested to see what you find.

 

[99Yota]

Good luck. I think I've exhausted the extent of my knowledge on these so I'm interested to see what you find.

Did you ever get this fixed?

I've opened up the actuator on a gx470 like this youtube vid:
If I recall correctly, if the gears aren't clocked correctly-ie actuator rod is pulled out too little or too much, the light will illuminate incorrectly. Like thezentree said. To clock the gears, you'll need to remove 2 gears and a plastic piece and extend or push in the actuator rod and reinstall the gears.

Hope the vid helps; the actuator pic you shared looks different than the 04Gx470 one I tinkered with as well as the one in the vid but the mechanics might be similar enough for the process to work.

GL!