Preventative maintenance for front diff actuator and/or center diff lock actuator

[NJ-4Runner]

Hey - I am a new member here and I have a few new guy questions. I just got this 2002 4Runner and while it is new to me I have some good wrenching experience under my belt.....especially with older rusty Toyotas! I had a 1987 4Runner for about 20 years that was an incredible vehicle but it eventually rusted to death...very sad demise. I have been crawling under the 2002 for about 2 weeks now getting it woods worthy. I had to replace the steering rack, lines, pump....etc., that was fun.

Overall the 2002 seems like a pretty well put together vehicle, but coming from the '87 some of the things I am weary about are all the electronic stuff, like the front diff actuator, the center diff lock, and there also seems to be a lot going on under the hood in regards to the ABS. Is there any kind of preventative maintenance for the actuators that I can do to assure that I don't have any problems getting it in and out of 4WD, and locking the center diff? Can I take the plastic covers off and clean the gears or spray contact cleaner in the little motors? Should I just leave them alone? Lastly is there an option to remove them or modify them to operate manually? Could I modify the actuator and put a bar of metal in there so I can go under the truck, move a lever to engage the front diff? Has anyone done anything liek that?

 

[Dieselchessy]

Preventive maintenance is described in the owners manual. Basically actuate the 4x4 and locker a few times each month and drive in 4x4 about 10 miles each month.

They make a cable actuator for the locker. Not sure I’ve heard of such an animal for the ADD setup up front.
You can swap in Tacoma manual hubs though. So at that point you could bypass the ADD and just use the hubs I guess.

 

[NJ-4Runner]

Preventive maintenance is described in the owners manual. Basically actuate the 4x4 and locker a few times each month and drive in 4x4 about 10 miles each month.

They make a cable actuator for the locker. Not sure I’ve heard of such an animal for the ADD setup up front.
You can swap in Tacoma manual hubs though. So at that point you could bypass the ADD and just use the hubs I guess.

Do you have any more info on the cable actuator for the center diff lock? I really looked around and couldn't find anything. All I found was info for manual cable actuation of the rear E-locker, no the center diff.

 

[Dieselchessy]

Not the center lock, the rear locker.

 

[Bad Luck]

Do you have any more info on the cable actuator for the center diff lock? I really looked around and couldn't find anything. All I found was info for manual cable actuation of the rear E-locker, no the center diff.

You can swap your multimode transfer case with a normal j-shift transfer case if you really want to eliminate the center diff option. As far as a manually selectable front diff actuator I don't think there are any. Only way to get rid of that is to retrofit tacoma manual hubs onto your 4Runner and either swap out the ADD setup or wire the ADD lever engaged and put the actuator cover back on.

With that being said. Just use your 4WD/AWD system often and you'll be fine. When it rains I switch it into AWD to get it some exercise. I make sure to use 4wd and my rear e-locker at least once a month.

 

[NJ-4Runner]

You can swap your multimode transfer case with a normal j-shift transfer case if you really want to eliminate the center diff option. As far as a manually selectable front diff actuator I don't think there are any. Only way to get rid of that is to retrofit tacoma manual hubs onto your 4Runner and either swap out the ADD setup or wire the ADD lever engaged and put the actuator cover back on.

With that being said. Just use your 4WD/AWD system often and you'll be fine. When it rains I switch it into AWD to get it some exercise. I make sure to use 4wd and my rear e-locker at least once a month.

Thanks. Nice to know the manual transfer case is an option. The center diff lock for my 2002 transfer case does not have an external actuator correct? It is more of an internal mechanism with some kind of solenoid right?

Is it common for these transfer cases (electric center diff lock) to develop problems?

 

[Bad Luck]

Thanks. Nice to know the manual transfer case is an option. The center diff lock for my 2002 transfer case does not have an external actuator correct? It is more of an internal mechanism with some kind of solenoid right?

Is it common for these transfer cases (electric center diff lock) to develop problems?

No external actuator. There's a shift motor that moves the 2wd/awd/4wd shift fork. Some people develop problems with the motor, but most of it seems to be related to not using it enough. They enjoy frequent exercise.

 

[phattyduck]

Is it common for these transfer cases (electric center diff lock) to develop problems?

Use it or loose it. They are reliable when used fairly regularly.

You'll see them non-working in trucks that were never taken off road.

-Charlie

 

[twitchee2]

Just use it. Every now and then as I roll up to a stop light, I will engage the transfer case while I am still coasting in. Pops in every time and I will drive it around town for a little while. Same thing with the center diff lock, just make sure you keep it straight or your are in the dirt and you will have no issues. Every now and then I will throw it in 4low as I am going through a drive thru for lunch (AWD mode, only) just to keep things moving around.

2002 with 306k on the clock

 

[phattyduck]

High/Low is all mechanical/manual and shouldn't need exercising.

Using 4WD keeps the actuators happy and keeps all the gears/etc. in the transfer case and front diff fully lubed. Even the j-shift (mechanical) transfer case should be shifted in/out of 4WD semi-regularly.

-Charlie

 

[3bears]

I exercise mine all the time...for me however...in winter...late october to march...my exercise is turning it off and putting into 2wd for a few miles...just to keep actuators and switches working
this time of year...well..i need 4wd at least once in a while every few weeks if im out exploring/fishing/hunting

 

[NJ-4Runner]

Use it or loose it. They are reliable when used fairly regularly.

You'll see them non-working in trucks that were never taken off road.

-Charlie

Just use it. Every now and then as I roll up to a stop light, I will engage the transfer case while I am still coasting in. Pops in every time and I will drive it around town for a little while. Same thing with the center diff lock, just make sure you keep it straight or your are in the dirt and you will have no issues. Every now and then I will throw it in 4low as I am going through a drive thru for lunch (AWD mode, only) just to keep things moving around.

2002 with 306k on the clock

I exercise mine all the time...for me however...in winter...late october to march...my exercise is turning it off and putting into 2wd for a few miles...just to keep actuators and switches working
this time of year...well..i need 4wd at least once in a while every few weeks if im out exploring/fishing/hunting

Thanks for the advice. Right now everything seems to be working perfectly. If I push the bottom it goes into 4WD right away and the center lock also works quickly after I press that button. This is not going to be my main vehicle, I am mainly using it for the woods and the beach, so it will be in 4WD more than 2WD. I will just be sure to hit the buttons fairly regularly.

When I researched and picked up the truck I didn't think much of the differential in the transfer case but I really like it for some of the woods riding I do. Some of the trails I drive in are very whooped out from quads and dirtbikes and the differential in the transfer case allows the truck to not lurch back and forth so much over the whoops (they are too deep to go over fast...you have to drive slow through them).

 

[AspenBob]

Check the breather hose

The transfer case actuator has a breather hose attached to it. If that hose slips off or breaks, water will get in and destroy the unit. Best to check it occasionally.