4x4 PSA: Use it or lose it monthly reminder
 

Here is a friendly Public Service Announcement:

Engage all your 4x4 features once a month and your truck will thank you for it by avoiding a hefty repair bill. A few minutes of free exercise every month will save you big $$$ in actuator repairs.


I've noticed a few more threads recently about 4x4 4th Gens with problems getting in or out of H4 (for the V6's), L4 or the CDL due to lack of use. The shift actuator rods seize up.
I had this same issue years ago but not as severely. I got lucky and was able to get the system to work just by using it. The more I used it the easier and faster it shifted in or out of the modes. I set a recurring reminder in my calender on the first day of every month to remember to engage the 4x4 system. I plan to bump this thread as required (plus it gives me a legit reason to be a post-whore.)

(I know this is a day early but I won't be near a computer tomorrow.)

#saveuractuator

I wish someone in the aftermarket would make a mechanical linkage kit to do away with the electrical actuator. You are right there are a lot of threads on actuator not working and actuator oil leaks. It is only going to get worse as the 4runners get older. I hope the 5th gens have been redesigned to correct the problem but when I look at them they look the same.

Ha ha, good title and reminder !

:amen:

Although in practical terms, I don't know how difficult it would be to actually create such a kit. Over on the Ford Ranger forums where I sometimes post (my DD is a 96 Mazda B2300 which is a Ranger) I see similar complaints about the electronic T-case, and somebody has come up with a "manual" solution.

The problem with it is that it requires you to

(a) stop the vehicle
(b) Get out
(c) reach under the vehicle with a socket
(d) turn a bolt 270 degrees or so and then
(e) get back into your vehicle and drive.

And you have to do this every time you want to go from 2wd to 4wd and back.

I seem to recall that somebody made a system for (I think) Chevy/GMC vehicles with vacuum or electric 4wd control that used a pair of cables, basically one to engage and one to disengage. This would have been back in the late 90's.

the ford system should be easy to make a cable actuator for.

I agree, and have said it a few times now, someone needs to come up with an electronic actuator eliminator system.
be it cable, or linkage. there has to be a better way to do it.

its one of the few things I really dislike about my 4runner.

If they came out with one that retained all of the capabilities of the current system (IOW retained the AWD/center diff capability) I would pay up to $1500 for such a conversion. Seriously.

Can't remember if it was someone here or someone at Home - ExPo: Adventure and Overland Travel Enthusiasts that actually replaced the T-case in a 4runner with an FJC case modified with twin stick (one for 2wd/4wd and one for Hi/lo.) He had the sticks come up through where the 12v outlet and smoker's kit come up.

I think if I ever had the dreaded electronic T-case failure, I'd be tempted to go with such a swap, especially if I was already looking at a ~$3k repair bill.

Of course, the only problem with that arrangement is that you lose the center diff and you basically have a conventional 4wd vehicle.

Last time I saw the Torsen Center Differential is non-electrical, so its "torque sensing" ability is mechanical in nature (its actually a planetary gearset). Now CDL is electrical but I believe (and I could be wrong as I haven't checked in a while) it is also managed by the shift fork assembly from the main actuator.

While a manual cable/linkage system could be fabricated, the main reason there's an electric system is mainly due to synchronization and ease of shifting. Now I'd have to have a transfercase apart to play with its guts, but I would assume even with syncros that any manual version would be a bit more difficult to shift into and out of 4WD modes.

The V6 would provide an additional challenge in that you need a secondary linkage that is either an entirely separate lever or somehow linked with the main assembly to actuate the ADD on the front axle. Now you could just eliminate the option of 2WD like the V8's and have the front axle constantly locked for a Full-Time 4WD effect like many do already (another option may be to eliminate the ADD and utilize old-school locking hubs in the front somehow,) but this is a design issue that needs to be addressed as well. There are also considerations to make in regards to leaving the front axles always engaged, while not as annoying or detrimental to driving manners as older Domestic 4WD systems, it does seem the V6 front axle does experience some minor bind-up when engaged in 4Hi vs. the V8's plain from clamshell (I also believe the V8 Clamshell in front is larger than its V6 brethren.)

The other issue is a matter of how you're going to control functions such as 2WD-4Hi-4Lo-4Lo CDL (if possible), this would require fabricating an entire shifter assembly that not only is compact enough, but bolts to the shift forks in the transfercase (the shift rods are actually part of the actuator and thus this hypothetical kit would require new shift rods that mate properly with the internal shift forks.) This of course brings me to another issue, whether you install this manual kit by using the old shift forks with new shift rods, or replace them with a new set-up (i.e. a new shift fork/shift rod assembly that allows servicing the shifter assembly without removal of the transfer case as is with the current actuator system), you still need to drop the transfercase and tear it down to properly install said kit, which would cost you additionally ontop of the actuator.

You'd also possibly lose/corrupt many of the ABS/VSC/TRAC functions that combine with the 4WD system to make it more capable that it is by itself due the the 4WD module needing to be disabled and the vehicle no longer being able to differentiate the difference between which 4WD setting it is in. Granted many people don't bother with the above assistance, but this could also result in aggressive over compensation from the ABS/VSC/TRAC system when you don't want it and would require you to disable most of those systems, which is difficult as it is heavily intertwined with the Hydraboost braking system used for your brakes and thus basic ABS/VSC functions remain even when doing "VSC OFF" mods because of fail safe coding.

As you shift into progressively lower gears in 4WD the system is aware of this and compensates with increasing its ability to assist. i.e. 4Lo, CDL On, Lo Gear nets you the most grip and even kicks in the ATRAC system to mimic a semblance of lockers in front and rear, this can be useful when you have 1 wheel in the air or are in very difficult terrain. Granted, many people rarely if every need to use these functions, but they work to subtly improve (typically, not always) the 4WD capability of the 120/150 Platform and thus using an add-on manual shifting system would possibly necessitate the installation of locker(s) to compensate for a loss of electronic assistance.

There are many design considerations to make and while I am sure it can be done (I'm seeing in my head little reason why it wouldn't work should the above larger concerns be engineered properly) it will end up costing you parts + labor to re-fit the existing transfercase. Thus no matter what you do, you still need to foot the bill to have the transfercase removed, torn-down, and then rebuilt (in the case of adding this manual linkage system, you'll need to find a shop that is willing to do the work; some may not due to liability reasons) so you're looking at an expensive modification/repair either way. You might just be better off getting an aftermarket transfercase or even trying to adapt an FJ cruiser manual transfercase (which may be easier to be honest.)

Is a V8 with full-time 4WD exempt from the monthly routine?
Or should V8's drop into 4Lo once, monthly?

I would still exercise it in both 4Lo and CDL ON once a month, the idea is to get the actuator to move so it doesn't seize up which is what typically happens.

As a noobie im going to bookmark this thread. Ran around a little tonight in 4wd because of this thread.

Probably a good place to mention that the diff lock can be exercised any time while driving relatively straight (super easy on V8).

Low range, of course, stopped and in neutral.

Having fun with it can be helpful in remembering and doing it often. Thanks to the Torsen diff, you can drive around parking lots in low range any time you like with no drama. V8 owners can quickly turn the CDL on and off just about any time they think of it while driving.

Once a month is great, but you can't exercise them too much.

Something else to point out is that the main reason Toyota doesn't want non-straight light driving with the CDL On is because it essentially becomes similar to older Domestic 4WD systems.

If you haven't had the displeasure of driving say an older Grand Cherokee or GMC SUV with 4WD engaged I'll try and explain it as best as I can. They have a LOT of axle bind-up and it sounds and feels horrible to drive them in anything BUT straight line. When CDL is engaged it locks the center differential and forces a 50/50 split from front to rear axle, so when turning that force is not only imparted between left and right wheel but also front and rear axle. While bind-up is no where near as bad as older systems, it still is noticeable and very hard on the 4WD system.

Thanks. If the weather and driving conditions don't cause me to go into 4LO and CDL then I'll do it as a monthly routine.

Your friendly April reminder.

I read somewhere on a recent thread that Toyota recommends running in 4Lo once a month for 10 miles or something. 10 miles!!! That unfortionately is not going to happen for some of us city dwellers.

I will usually engage 4Lo and slowly drive in my work parking lot for a minute or so. Is that adequate?