Stupid 4wd question?

I've had my 2016 TRDOR for 3 years now.
My other truck is a 1977 International Scout SSII that I've had for 32 years.
I know that there is a pretty substantial difference in the 4wd systems between the two.
The Scout having manual locking hubs and a manually shifted t-case.
My question is whether or not the front axle on my Tacoma is always free spinning as if it had
hubs that were locked but the t-case isn't in 4wd?
I do that with my Scout every now and then to keep the front diff lubed.

 

Per the manual you should drive 10 miles a month in 4wd to keep everything lubed up

 

Its not spinning when disengaged.

You’ve got to post a pic of the Taco and Scout together!

 

So, do the hubs lock in only when torque is applied?
If so then it's similar to the old LOCK-O-MATIC hubs.

 

I assume your Scout is a solid front axle, your Tacoma has an IFS independent front axle system. One CV axle on either side of the front diff.

With IFS the CV axles are constantly spinning on Tacomas even in 2wd because of the ADD system. With manual hubs, when they are unlocked the axles do not spin.

Part of the reason some people do manual hub conversions on their later model Tacomas. It can be argued that CV axles constantly spinning adds wear and tear to them over time even though 4wd isn't engaged. But, CV axles on ADD Tacomas are beefier than the CV axles used on manual hub Tacomas (back when they used to make manual hubs on Tacomas anyway).

That being said, just because the CVs are spinning does not mean you're properly working the 4wd system...to keep it lubricated and functioning reliably you should exercise it by putting into 4wd on the *appropriate surfaces every now and then

* cue endless TW debate about 4wd and surfaces

 

No. The hubs are “locked” all the time. Toyota uses an ADD system, like most others do these days.

The best learning guide out there:
https://m.youtube.com/watch?v=47m7QAPrpsI

 

Isn't that also called a center axle disconnect or something like that?

https://www.tacomahq.com/4546/toyota-tacoma-4-wheel-drive-explained/

 

No. The device that allows the front wheels to freewheel is the ADD device, which resides in the passenger side axle front tube. It is separate from the transfer case. That video is long and somewhat boring, but lays it all out. You will be an expert if you sit through it. Might save your ass on the trails.

 

I stand corrected. In the info you provided they do call it a center axle disconnect. I’ve always heard of it referred to as ADD.

My apologies.

 

Hey, don’t accept an error without checking the reference I sent first! It may be in error, not you.

I will have to watch the video, to be honest I’m really not that familiar with the newer Tacoma 4WD system. Back in the old days, we had to twist stuff like screwdrivers, keys and hubs to get things to work, not push a button!

 

I really like that video, and the fella that does them. I think he’s a teacher of other mechanics. I believe he’s in a wheelchair. Anyways......we’ll worth the view. He goes into the ADD in depth in the second half of the vid.

It is good to understand how the truck works, even if you are not working on these systems yourself. Can really help when you are trying to figure out what’s Fubar.

 

You know what? The Center Axle Disconnect is the same thing as Toyota calling it the ADD or Automatic Disconnecting Differential.

Good video, thanks!

 

Good video. Learned a few tings.

 

I've been researching converting to manual hubs to eliminate the constant spinning. Do you know of any kits on he market?

 

I don't know of one for 3rd gens...I know there's a kit for 2nd gens or at least there used to be, but I don't know if it would work or not.

The CV axles spinning all the time isn't necessarily going to hurt them unless you have a lift to where the boot fins are rubbing, then they'll rub apart in short order.

 

Thanks for all of the great info everybody.

 

Here you go Bob.

 

Nice rig!

 

Just a note that the 2Lo Mod (2LM) is shipping out:
https://www.tacomaworld.com/threads...-2wd-low-range-for-the-3rd-gen-tacoma.614743/

Installed it yesterday and is just freaking stellar. It will mostly do what putting it in 4Hi without locking the hubs does. You just want to be sure to cycle it into real 4Hi every once in a while to keep the ADD actuator happy.

Also, there are manual hubs for the 2nd and 3rd Gens:
https://www.tacomaworld.com/threads/free-wheel-hub-conversion-3rd-gen.513930/

 

Very nice! Thanks