Front Differential Actuator Disassembly - Pics

[scw1991]

Thought I'd share as a picture is worth a thousand words.

The motor was seized up on this and one of the motor terminals came unsoldered. I disassembled, dropped a dab of oil on the motor bearings to get the motor shaft to spin free, and resoldered the terminals.

 

[Kmvreter]

Thanks for the info. Hope I never need to use it but good to know.

 

[Hongster]

Thank you, that's awesome. Very nice job!

 

[BlackWorksInc]

Nicely done!

How did you time the motor and how well does it work in the vehicle?

 

[scw1991]

Blackworks,
have not had opportunity yet to bench test this ADD. I always request any old parts be given back to me so I can disassemble and try to figure out why they fail. I'm just amazed this motor shaft seized up from lack of use.

It sounds like this ADD and the transfer case actuator are the achilles heel of any 4th gen Toyota and higher utilizing these components.

If I can find a 4th gen transfer case complete with actuator cheap enough one day, I'd buy it just to disassemble and understand the inner workings of it.

 

[Brutalguyracing]

Does anyone know the part numbers of driver and pass side oil seals for the front diff..
03 v8 limited?

 

[nvestor88]

Does the actuator on the transfer case come off easy, like the ADD?

 

[Izlu]

Does the actuator on the transfer case come off easy, like the ADD?

No, the transfer case needs to be teared apart

 

[scw1991]

it looks like some folks here on the forum are making some headway to rebuild the transfer case actuator and/or replace the leaking o-ring seals without actually cracking open the transfer case.

But to answer your question, the actuator shift rods are held in place by c-clips inside of the transfer case. So no, you cannot remove the entire actuator assembly without performing a transfer case dis-assembly.

 

[mb66]

Just wanted to give thanks to scw1991 for documenting all this. Recently had a 4WD (non)engaging issue with our '06 and this was exactly the culprit. ADD was clean inside but the motor was seized. I put gun oil on the bearings, sprayed some extra silicon lube in it as well, and soldered the motor leads.
Viola.

But for this I would have taken it to a dealer for repair. So again, thanks.

 

[04rnr]

reviving an old thread....
Im thinking about trying this, seems simple enough, but I know me lol...

scw1991, Thanks for posting this, and the pictures.. :thumb:

 

[Nickname]

Blackworks,
have not had opportunity yet to bench test this ADD. I always request any old parts be given back to me so I can disassemble and try to figure out why they fail. I'm just amazed this motor shaft seized up from lack of use.

It sounds like this ADD and the transfer case actuator are the achilles heel of any 4th gen Toyota and higher utilizing these components.

If I can find a 4th gen transfer case complete with actuator cheap enough one day, I'd buy it just to disassemble and understand the inner workings of it.

Reviving this thread. Was there any resolution on how to time the ADD? If the ADD is out of the vehicle, and it is opened carefully, will all the gears fall out or are they help in there?

I am having a similar problem with 4hi not engaging. Swapped in a new transfer case and actuator and am still having the problem. From looking at the 4wd sequence I think the ADD is the culprit. I have a new ADD in case I can't fix mine, but fixing my current one and sending back the new one would be cheaper. Appreciate any help!

 

[Hi-desertT4R]

Reviving this thread. Was there any resolution on how to time the ADD? If the ADD is out of the vehicle, and it is opened carefully, will all the gears fall out or are they help in there?

I am having a similar problem with 4hi not engaging. Swapped in a new transfer case and actuator and am still having the problem. From looking at the 4wd sequence I think the ADD is the culprit. I have a new ADD in case I can't fix mine, but fixing my current one and sending back the new one would be cheaper. Appreciate any help!

No, the gears won’t fall out when you take the cover off the actuator. As far as timing you just need to make sure the shift fork is in the unlocked or open position (all the way to the passenger side). You can use a 9v battery to test the motor in forward and reverse. I had this 4WD issue and ended up soldering the motor leads together. No issue since. Be sure to lube the gears with white lithium. Make sure the collar in the ADD tube moves freely and the fork engages properly when reinstalling. Also check the rubber hose to make sure it’s not split open or damaged.
Some guys say they’ve had issues with the screws stripping so be careful there. See pics. Red arrows where I soldered.
Hit me up if you need clarification or have questions.
No 4WD 4hi and center lock flashing

 

[Nickname]

No, the gears won’t fall out when you take the cover off the actuator. As far as timing you just need to make sure the shift fork is in the unlocked or open position (all the way to the passenger side). You can use a 9v battery to test the motor in forward and reverse. I had this 4WD issue and ended up soldering the motor leads together. No issue since. Be sure to lube the gears with white lithium. Make sure the collar in the ADD tube moves freely and the fork engages properly when reinstalling. Also check the rubber hose to make sure it’s not split open or damaged.
Some guys say they’ve had issues with the screws stripping so be careful there. See pics. Red arrows where I soldered.
Hit me up if you need clarification or have questions.
No 4WD 4hi and center lock flashing

Ended up replacing the ADD. I pulled my skid and the breather was cracked and no longer attached to the ADD. When I opened up the ADD a bunch of muddy water came out. Motor was very corroded. I already had a Aisin replacement from rock auto so I didn't mess with the fix. I might mess with it later, but winter is upon me here in CO.

Update: The Aisin ADD shifts SUPER smoothly. My 4wd was quick to shift in before, but now it is quick and quiet. Glad this was the fix. Got a pack of hose clamps and will be adding them to all my breather connections. The breather tube was starting to crack on my T-case as well!