VF4B Transfer Case Swap

[Engineer]

Not seriously considering this in anyway, just "thinking out loud". Interested to see if anyone has any information or thoughts that I don't or a good source of info. Please do not ask "why would you do this"....I am not doing this, just a thought provoking activity. Sorry this is interlaced with facts and questions or if some information is wrong I did not research thoroughly

*Edit, comments to get an aftermarket case or SAS swap are also not the intent.

There are 3 different transfer cases that have come in the 5th Gen 4 runners.

VF2A - Lever actuated part time case ( All Trail Editions and Pre?? SR5 )
VF2BM - Dial (electric) actuated part time case ( Post ??? SR5 )
VF4BM - Dial (electric) actuated full time (torsion center dif) case ( Limited )

Toyota also has a VF4B that is a full time (torsion center dif) lever shifted case found on the 6sp MT FJ cruisers. Tacoma's also come with the VF2BM

Thoughts of what would be needed for the swap/questions:
*The VF4B Case from a MT FJ
*4x4 ECU (likely from a limited, not sure if it would play well with the locking rear dif. or if they even run through each other)
*Are the case input shafts the same spline size?
*Are the case dimensions the same?, it appears that the VF4B/VF4BM is longer then the VF2A to accommodate the torsion center dif. Not sure if this effects both the front and rear driveshaft lengths.
*Need to either remove or permanently engage the ADD system.
*Gauge cluster, it doesn't appear that my 2014 Trail P. has the indicator light or diagram for the center lock dif. ( again this may be an issue as if you swapped with a limiteds it likely wouldn't have the KDSS light) ,I tried looking with a flashlight and didn't even see an "outline" for the diagram

 

[Orc]

Get an atlas case trans and some beefy diffs.

 

[BlackWorksInc]

That sounds about right, if the vehicle is already 4WD; then the list sounds correct. Don't forget about the interior trim panels/ect. to complete the swap if you're changing from lever to switch or vice versa.

 

[1engineer]

Why would you do that lol. Had to ask just because...

 

[Antman]

Why would you do that lol. Had to ask just because...

Within the next 15 years someone will do this.

You engineers always plan too far ahead, lol.

 

[Orc]

I could understand if something was broken but why spend money to go from stock to stock. Is the dial case weaker than the manual shift?

 

[BlackWorksInc]

I could understand if something was broken but why spend money to go from stock to stock. Is the dial case weaker than the manual shift?

People think it is mainly because of the electrical components that could potentially fail. But the cases are built similarly in terms of strength, its just one has an expensive electronic actuator to move the shift forks and one has a lever.

 

[Engineer]

I don't think that the cases VF2x vs VF4x are any stronger or weaker, once just seems tohave been designed to accept a center differential.I was hoping this would spur interesting discussions as there is no "how to" on this out there......guess I was wrong :crutch:

 

[96r50]

I don't think that the cases VF2x vs VF4x are any stronger or weaker, once just seems tohave been designed to accept a center differential.I was hoping this would spur interesting discussions as there is no "how to" on this out there......guess I was wrong :crutch:

It would be interesting to see if you could swap the full-time case from a Limited into a Trail or SR5 with minimal changes. I think the hardest part would be figuring out the electrical system to prevent the dash from lighting up. You would also have to "lock in" the ADD in the front end, or replace it with the regular front diff from a Limited.

There was a member (bjowett) on one of the Tundra forums who took the full-time 4WD centre differential from a 200 series LC and installed in his Tundra. From what I remember his install went fairly well as both of those vehicles share a similar drivetrain. It would certainly be interesting to see whether this could work for the 4Runner platform. I don't know that I'd ever do it but researching it is half the fun!

 

[derekwilliams345]

So is there a part-time case with a torsen diff?? Id really like to keep 2wd

 

[RonJR]

So is there a part-time case with a torsen diff?? Id really like to keep 2wd

The VF4AM that went in the 4th gen V6's does what you want. It's called "multimode" and has 2wd, 4Hi with torsen center diff, 4 Lo with Torsen center diff, and ability to lock the center diff in both 4wd ranges. Pretty much does it all. Not sure why Toyota dropped it for the 5th gens.

 

[derekwilliams345]

The VF4AM that went in the 4th gen V6's does what you want. It's called "multimode" and has 2wd, 4Hi with torsen center diff, 4 Lo with Torsen center diff, and ability to lock the center diff in both 4wd ranges. Pretty much does it all. Not sure why Toyota dropped it for the 5th gens.

And for the most important question... Can i get the VF4AM with lever actuator?!?
And additionally, considering the vf4am was used behind the A340F on the early 4th gens, doesnt that mean it should bolt behind my R150F??

 

[RonJR]

With enough tinkering and some machining, you could probably get where you want to go. There is really very little internal difference between the VF4A and the VF4B. The difference is primarily in which shift rods/forks are installed and which are left out or permanently fixed inside the case. If you had a VF4AM(electric shift multimode) and a VF4B (manual shift full-time 4wd) lying on your bench, I'll bet a clever person could combine the two to make a manual shift multimode case. Might have to machine up an extra shift rod and tweak the manual shift levers.

But, realistically, the small mpg gains from having true 2wd probably aren't worth it, unless you're just fresh out of project ideas and need something to do.

 

[BlackWorksInc]

I've thought about tossing a V4FB from a FJ or GX470 into my V8 4th Gen, but I'd still have an electric actuator for the CDL function, so it's not entirely worth the trouble.

 

[phant0maz]

If you had a VF4AM(electric shift multimode) and a VF4B (manual shift full-time 4wd) lying on your bench, I'll bet a clever person could combine the two to make a manual shift multimode case.
.

Old thread but I'm on this subject right now. So after reading this post I started thinking is that really true. Here where I live it is easy to find vf4b transfer case but is it true that it can be converted to part time t case? I mean are both cases internally identical with differences only in the shifters?

Another question I can't find an answer is: VF2A found in automatic transmission FJ cruiser - does it have LSD Torsen differential or not ,and which type of Torsen it is. A, B or C? Anyone?

 

[Jackedup4runner]

My thing is, i got a 2010 limited. Its lifted. 35s. Gears, arbs, supercharged yada yada. I hate that its awd. I would much rather swap to a tcase that keeps the truck in true 2wd until i put it in 4wd.

 

[Rescue Runner]

Ok I know this thread is older but maybe people still check it?
I am working on building a parts list for my wife’s Tacoma prerunner we are gonna do a 4x4 swap on. Before you say just sell it and buy a 4x4, we have to much into her truck and got it for cheap so it would not be worth the extra money to sell and buy new then upgrade everything again.

My question is does anyone know if there is a difference between VF4AM and VF4BM other than they bolt to different transmissions? I know VF4AM goes behind A340F And VF4BM goes behind A750F. My reasoning for this question is I want AWD as an option but having 2wd would also be good if possible. Looking at a 4Runner http://www.toyota120.com/GenDocs/2003_4Runner.pdf
I see the only difference is the V6 model with VF4AM has ADD on front axle and V8 with VF4BM has solid tube front axle. Is the ADD the only this that disconnects to make V6 4runners 2wd capable? I have searched and searched and not been able to find a definition of the physical differences in transfer cases other than they bolt to different transmissions.

 

[RonJR]

In order to not have the front driveshaft spinning in 2wd, the front drive shaft must be disconnected at the differential (ADD) AND at the tcase (2wd/4wd). Thus, the two transfer cases are slightly different. The VF4BM has two shift rails, for high range/low range and for center diff lock. The VF4AM has three shift rails, for hi/lo, center diff lock, and for 2wd/4wd. There is logic inside (either mechanical or in the electronics of the shift controller) of the A version to lock the center diff in 2wd. Otherwise, when the front output shaft is disconnected in 2wd, the center diff would just spin uselessly and you wouldn't move.

I don't know for sure if the internal gears/collars, etc., are any different between the A and B. It might just be that the 2/4wd rail is shortened (so it doesn't exit the tcase) and permanently locked into the 4wd position on the B version. I've looked at the exploded view in the FSM but never been able to truly tell exactly what's going on.

 

[Rescue Runner]

Thank you. Sounds like you have come to the same conclusion as I have.
Do you have any knowledge of anyone wiring up a VF4BM without use of 4WD ECU? Like homemade harness that just supplies power to The shift motors to lock or unlock center diff or switch in and out of low range? Looking at doing this as my wife would prefer have AWD over 2wd and locked 4x4

 

[Jetboy]

There's a lot of good info in here:
https://atracom.blob.core.windows.net/webinars/import/toyota_4x4.pdf