G2 4WD Actuator

2008 Tundra

When I spin the 4wd dial on the dash to 4-Hi all I get is a flashing 4Hi light. 4wd does not engage. Low range does not engage.

I've tried the "tapping" on the 4wd actuator at the rear of the t-case. No love.

I can hear no audible indication the actuator motor is trying to work other than a relay click inside the truck.

4wd fuse under the dash is fine and has continuity.

I did remove the actuator guard and popped off the bottom cover of the actuator to have a peek. I know this is the low range motor but the screws to the top cover are rusted solid. Not much room to work there so I left it be for now. But when I removed the lower cover/motor there was water inside the actuator. Not a lot, but some. Metal bits did not appear to be rusted/corroded. The low range motor tested fine.

So my question is two-fold. The actuators are expensive and I'd really like to confirm the actuator is dead before ordering a new one. Since the screws are rusted solid on the top motor housing, I'm confidant I'll have to destroy the housing to remove the actuator.
1) whats the best way to conform the actuator is dead? Computer? Anyone have a pin out location diagram?
2) if both motors are removed from the actuator box, can I remove/install the actuator without disassembling the t-case?

 

There's two actuators. There's on on the transfer case and a second one on the front diff. I believe the transfer case one activates first and then the front diff. If it's the transfer case you might be able to take it apart but to actually remove it means pulling the transfer case apart. That's not a job for a novice. You can check around for a used transfer case. Since they don't usually go bad they aren't too expensive. I think the front diff one can be replaced.

I would think the easiest thing to do would be to switch to 4wd while driving to give it the best chance to go in and then set the parking brake/ put it in park. Jack up one front tire and try to spin it. If it spins (which it will if you aren't in 4wd) look to see if the front driveshaft is spinning. If it is then the transfer case is in 2wd. If it isn't I would verify that the front driveshaft can't be spun by trying to turn it by hand. Just make sure you use a jack stand or something better than just the jack before crawling under the truck. Also if you've run the truck for any length of time the exhaust could be hot and is close to the driveshaft. If the front driveshaft feels like it's in gear then your problem is in the front diff.

 

It’s definitely not Shifting into Hi-Range. I’ve tried everything....rolling, bouncing, warm, cold, etc...Not happening.

I have a 2-post lift at home. While on the lift I can get under the truck while someone turns the switch. Nothing is happening inside the box mounted to the t-case. So either the motor is dead or it’s not getting signal. I can’t find a wiring diagram for these related plugs.

Pultruding from the transfer case are two rods - hi range and low range shifters. Those two rods/shifters enter the actuator box. I can understand why you cannot remove the actuator box without disassembling the transfercase because those rods are secured inside the transfercase. But if I remove both motors from the actuator, unlocking the rods/shifters, I guess I’m not understanding why the box can’t be removed from the transfer case, just leaving the shifters connected inside the transfercase. Can someone explain?

 

I think the box can be removed but it's the timing that poses an issue. The motors drive gears that have metal contacts. Everything needs to be in the correct location when you put it back together. I've never taken one apart so I can't say how difficult it is. Chances are your problem is something is corroded inside it and will not move. I've seen videos on other Toyotas where the box was taken apart, parts cleaned up, and reinstalled to get it working.

 

Finally tore into this thing. I tried all I knew to do to confirm it was the actuator box that had failed before ordering the parts. I suspected my problem was with the box, but was not 100% certain. So it was a bit of a gamble that paid off.

My biggest diagnosis problem was not being able to open the actuator box. I was able to remove the lower half (low range motor) but the screws securing the top half of the box were rusted solid. And with only about 4" of room to work between the top of the box and the truck cab floor, there isn't much that can be done.

I ordered the part from Rock Auto. $570.00 was the best price I could find. This part seems to be pretty much identical to the Toyota part - same cast marking on all plastic and metal parts.

To replace the box it is said you have to disassemble the transfercase. F'ck that. If something were wrong with one of the linkage rods, sure. However in my case I was pretty sure it was a non-working electric motor. Which it was.

To remove the old box I had to use a hammer and chisel to snap the box where the screws held everything together. This was super easy to do. 5 screws. Once I removed the top cap with motor assemble, I saw the problem.

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Once the top and bottom motor assembles were removed I took note of the linkage shaft locations. The motor assembly gears are timed with the linkage shafts. If the gears are not lined up correctly, as mentioned in the post above, it's not going to work and you'll need to realign the gears on the shafts.

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When you carefully crack open your expensive new part, take note of those shaft locations, too. When you reassemble the box using your existing shafts, you'll be able to adjust the shafts by hand to match the gear orientation on your new box.

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If you put everything back together and it's not working, you'll get a light on the dash:
Flashing Hi light = misaligned top motor assembly
Hi light ON but flashing Low light = misaligned bottom motor assembly
Flashing LOW light = misaligned bottom motor assembly

Here are some additional photos just for reference:

Bottom motor (low range and neutral motor assembly)

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Top motor (Hi range motor assembly)

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Actuator box with everything removed:

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Very nice info, thanks for sharing

 

This thread was very satisfying. Thank you

 

Timing took me forever. Just wanted to share. For 4 hi actuator.

 

I had a few questions regarding removal and installation of actuator

LMK if this is correct BEFORE I attempt.

Removal
1. Select 2wd button.
2. Remove covers on Low range and High Range motors.
Will this allow me to then unbolt and slide housing from transfer case while leaving control rods in?

Install
1. What position are rods supposed to be in? I've seen elsewhere they're supposed to be all the way in?
Also found this thread where someone noted it does not matter what position gears are in, the unit will self adjust?
https://www.tundras.com/threads/cou...case-actuator-replacement.50162/#post-1309491

Awesome, thanks for that. I figured that out as well, and then confirmed it was in the right position by plugging the wiring harness into the actuator but leaving it disconnected from the housing, then turning the truck on and switching between 2H/4H. The actuator will reposition itself to proper timing this way using it's position sensors. I even pulled the gears out and installed them randomly, plugged the actuator in and turned the truck on, and it immediately reset itself into 2H. Pretty nifty workaround! Thanks for your help, hopefully we saved someone some time and money!

 

As for question #1, I don't know. I really don't know that it matters if you're in 2wd or 4wd. I may be wrong but I don't see where it matters.

Question #2. Correct. Just remove the covers, motors, and the box/housing will slip right off after unbolting. This saves you from having to disassemble the t-case.

When installing the new motors, ha, I don't know of a sure-fire way to get it correct the first time. For me it was trial and error. Maybe someone else has a better way of figuring it out. But one thing I know for sure is they will not self adjust. Not on a Gen2 anyway. The gears can only spin so far before a tension spring stops the motor from spinning - if the t-case is not locked/unlocked by the time the gears stop spinning it's not going to work. It's just a matter of timing and not hard to do, just may be time consuming if you don't get lucky.

 

i'm thinking about tearing into mine. i never have issues going into 4hi, but 9 times out of 10 it won't go into 4lo. i hear a sound like a motor "trying" to move but it doesn't complete the cycle and i get stuck with a rapid blinking 4lo light that only gets reset when cycling the key.

also if i leave it in 4hi, there have been many occasions where the next time i start it up, the 4lo light is also blinking rapidly. when it is in this state, it won't let me switch to 2hi until a key cycle (sometimes several) clears the blinky 4lo

anyway, when i find some time to open up the actuator, i will post here again, but hoping my symptoms sound familiar to those you guys may have been experiencing prior to fixing it.

thanks

JB

 

Thats a new one on me. I wheel with a lot of tundras and Ive seen many weird 4wd problems on the trail, but havent seen/heard of those symptoms.

sounds like a problem with the 4lo actuator although having it blink when you're in 4hi doesnt make much sense.

Def keep us posted

 

I took mine apart because 4hi would not engage. The bottom actuator seemed fine, but the top actuator motor was locked up. Also this switch was broken. I got the motor unfrozen and working but this switch is broken. Any idea what it does? I do not have any lights on now, but I’m scared to engage 4wd now in case that’s a limit switch.

 

What a rusty pile of

God I hope mine doesn't look like that, but I haven't opened it yet. 4lo worked perfectly this weekend ( for a change)

Seal failure without a doubt

 

LOL that one is not mine. I did not take pics, i was just trying to highlight the switch that was broken in mine.

The shop that replaced my trans did not reconnect the vent tube to the upper actuator and a small amount of moisture got in. nothing near that. I am wondering why that vent is even necessary?

 

I've attached a tutorial I compiled when I fixed mine. And here's a link to another thread on this same issue:
2007-2020 Transfer Case Actuator
Discussion in '2nd Gen Tundras (2007-2013)' started by sixweeds, Jan 29, 2020.

 

Thanks man very helpful!!!

@papasmurf check out this doc

 

this is amazingly helpful as i think my 4-lo side may be corroded. it works when warmed up, but i still have many issues and have been hesitant to open it all up.

thank you for this tutorial with pictures!

 

You are my hero!! Thanks!

 

Hoping this thread is still being watched, because I am in need of some outside thinkers.

Short story - did the Transfer case actuator replacement yesterday. Got everything put back together with NO 4HI flashing and NO 4LO flashing. Went for a quick trip around the block. shifted into 4HI - 4HI starts flashing. Went back and forth - no change - until I was pulling back into the drive way and 4WD engaged. I could tell as the truck 'binded up' as I TURNED into the driveway while coasting. Tired and done for the day. I parked it.

This morning, I had a plan to figure out what was going on - but!!! It was foiled! I got into the truck - turned the key to ON - and the actuators did their thing - and the best way to describe what happened was - it was like removing the emergency break on a hill when you are in park - The truck was 'freed of some pressure' and rocked into park (It was already in Park - again - I just turned the key to on.) At this point, it felt to me that 4wd was now disengaged. I maneuvered the truck into the drive way, and jacked up all 4 corners so I could do my troubleshooting. As I thought - the front wheels were not engaged. 4HI still flashing - but HERE is my concern. In Drive and 2WD, when the accelerator is juiced a bit - there is a horrible noise that SOUNDs like its coming from the front differential. Clackity clank - It does not stop. Swithching to 4HI and back does nothing - still flashing 4HI. Now - keep in mind - the truck is suspended off the ground - no wheels are touching. When I replaced the actuators on the transfer case yesterday, the front wheels were on the ground and the rear wheels were on ramps.

I guess my next step might be to go back on the ground, and then investigate the position of the top Actuator (4HI) to ensure it is still in alignment. Any thoughts from you all would be most welcome!!

 

Helloworld, Your situation is a bit difficult for me to understand. But, let me see if I can summarize: You replaced the 4HI and 4LO actuators? Why did you do this in the first place? It wasn't going into 4HI or 4LO? If so, did you drop the transfer case and split the cases and remove and replace the actuator motor housing and rods? Or, did you just replace the actuators without removing the T-Case? If you go back through this thread, you'll see that I only had to free up one rusted motor in the 4HI side, and then reassemble the actuator motor housing. I never removed the T-Case or the actuator rods.
Nevertheless, you replaced the actuators and now it will go into 4HI and 4LO, but there is a horrible noise coming from the front axle/diff? Is that right? I might be more helpful if I understood your problem.
Thanks

 

Thanks for responding. To answer your questions - In the beginning, it would not go into 4HI - No movement in the transfer case actuator. I ordered a replacement part as the screws for the upper and lower actuators were completely rusted into blobs - I knew I would have to mangle the housing in order to remove the existing actuators. Removed everything except the two rods sticking into the transfer case. Put back in working actuators and got everything lined-up and working - (as in NO FLASHING LIGHTS when ignition turned to ON and in 2WD). When I attempt to go into 4HI - the transfer case actuator engages, and the front diff. actuator makes noise - but still no 4wd (and lights return to flashing) My guess at this point is that the front actuator is also defective - although it IS making noise. That is what I will be investigating further this week.

 

What did you end up riding out?

 

Hey Sixweed - I'm guessing your post should have read "What did you end up finding out?" Not sure exactly where to pick back up, but I can share - after multiple attempts - I finally got it to work! Temporarily. I think I must still be off by a gear tooth or two. What is happening now is that it will shift into 4HI, but when I shift OUT - the 4wd disengages BUT the light stays on and then starts flashing. It takes DAYS of multiple on/off cycles before the light will stop flashing getting me back to square 1. I am about to sell the beast and at this point will do so stating that 4x4 works, but you have be patient get it to turn off so you can use it again. If I have time, I may look to crawl under again to adjust. Anyway - this site - and thread - rock and saved me $$$ so thank you! I'll post the link once I have the full write-up for my ad. In the meantime - anyone interested, PM me. 2008 RCSB 5.7l BEAST with 4x4 (sometimes), SR5 and Sport Package (body colored bumpers) with 125k miles.

 

Glad it helped. Things that can be taken apart and fixed aren't anymore. They are just replaced for exorbitant amounts. Toyota wanted $7k to pull and split the T-Case and replace the actuator with a new one that costs $1.5k. It can be fixed for free or replace the motor with one from Ebay. Good luck on selling your beast!

 

Hey everyone, I was hoping someone could provide the part number for the high/low and 4wd motor assemblies. I've found some links but the parts images look different than what we have on our trucks. I pulled both off after finding that the breather line was completely off and they were both slap full of water. Thank You

 

Since I fixed my rusty motor on the 4WD Hi side of the actuator, I didn't need to replace the parts. I tried looking on Rock Auto and on Toyota Parts Online, but couldn't locate the specific part number. Sorry that's not helpful. Good luck!

 

where is the breather on the transfer case? On the top? (just out of curiosity)

 

No worries bud, I was able to find and order it. For anyone else wondering the part # is it's AISIN SAT013 for around 600$.

OEM from toyota was ranging between 1,100 - 1,500$ for the same part.

 

You talkin about the line for the actuator motor bud? I want to make sure I answer your question correctly lol