Is there a 2LO Mod for 3rd Gens?

This came up in another thread and I would like to have it for my TRD OR 6MT when starting out up a steep grade with the trailer in tow. I can find many write-ups for the 2nd Gen. Has anyone got a bypass for the front diff working for our trucks yet?

 

Currently no known method to achieve 2LO in the 3rd gen.

 

Not on topic but for thought I'd love having mts work in 4hi would really be cool to use the snow settings in the winter

 

Yep, 8 bolts.

 

You don't get any errors engaging the transfer case?

 

Actually no. I would of thought the VSS would have thrown a code after seeing different wheel speeds while in 4wd.

Shaft has been reinstalled, no more 2wd Lo

 

Oh really, why not leave it off.

 

What is the sticking point? Is it canbus integration? Are there people trying to get it working or is it just that no one has gone in hard after it yet? It seems like something that should be just disconnecting a motor and faking a signal that says "engaged".

So... follow-up question... where do I get schematics for this truck so I don't have to build a driveshaft with a locking bearing in the middle ?

 

I'm thinking will be a bit more than that since similar issue with the any time locker still not being capable. I think a lot of the computers limit said things now

 

I'm pretty sure the issue is integration with the BCM/ECM. To be honest I don't think it's been pursued that seriously.

If you want to try to do it yourself @gearcruncher can maybe help with schematics...

OA

Edit: I was reading this as a locker anytime mod - not a 2low mod (been a long day). We need a center diff, driveshaft disconnect or another case to do 2low. Not just electronics.

 

What I am calling 2LO is fooling the electronics into thinking the front diff is engaged when it is not so that the 4LO switch allows me to use the lower gear ratio but only drive the rear wheels so it does not bind up in the middle. THat way I can turn the truck while towing heavy in steep uphill stop/go situations. What I'm after is to simulate what used to be done on trucks with manual locking hubs... by just not locking them. My thinking is that there is a motor or solenoid on the front diff that needs to be prevented from engaging, and then something needs to lie to the computer and say that it's engaged. Then, when you switch back to 2H stop lying to the computer. It seems simple enough in my head but ... if all the communication is messages on the bus instead of current control it will require hacking the canbus system. Which might be beyond my reach without a steep learning curve.

 

I figured out a 2LO mod for my Ranger several years ago when the auto hub lockers sheered off. Replace your hubs with manual locks. When 4LO engages the shaft will spin to the front, but if the hubs are unlocked it won't matter.

I guess this is also dependent on whether manual hub locks are available for the 3rd Gens.

EDIT: Wrong gen, but these: https://www.summitracing.com/parts/...BzdqyuEavWcT_8WHYzmarYzJdUrm7G7oaAq3REALw_wcB

 

https://www.tacomaworld.com/threads/manual-locking-hub-conversion-kit.470056/

 

There's no way to electronically fool anything. It's physically shifting to lower gears, which engage the front driveshaft. You'd need a twin sticked transfer case and reduction box or manual hubs to do what you want. Or just remove the driveshaft like above.

The knob on your dash is doing the same thing a floor shifter would do...

 

@specter208 That looks like it would work. All I need to do is unlock them when I want 2LO and leave them locked 100% of the rest of the time. Let the truck do it's thing

Right - but the front diff is where I expected the 4x4 engagement happens? So, if that engagement doesn't happen but no error codes are thown... it's not driving the wheels and so... poor man's 2LO. No binding when turning but we get to use the lower gear ratio.

Unless the front driveshaft engagement happens in the xfer case. In which case... REALLY? Toyota spins everything all the time such that the front wheels are driving the front diff and driveshaft when it's in 2WD? THat is so wasteful of power and wear that I hadn't actually considered it.
.

 

Front driveshaft engages/disengages in the xfer case, and the front axle also has an internal disconnect. I read it somewhere, but cannot remember which happens first when you select 4 Hi..

 

...the manual hubs are your only option next to removing the shaft.

ts not toyota its majority of 4x4 now days are all like that. Honestly never looked into it if its still the same or an option etc, but only vehicles I ever seem to see with manual hubs still are 3/4ton + Fords and Rams. And no clue on year just look like newer ones.
I'm not sure if its always engaged though, I could be wrong but I know on mine I can spin the front drive shaft with the truck in park on the ground, and I can spin each front wheel with only one off the ground while in park as well. Never tried it in 4x4 though only 2hi.

And there's a lot of people that say leaving manual hubs locked all the time can cause damage or something.
Personally don't know for sure, never had locking hubs but really wish we still did.

 

When you shift the T case to 4wd, the ADD engages. Even if you disabled the ADD and managed to shift to 4lo, you'd still have drive to the drivers side front tire.
http://www.off-road.com/trucks-4x4/tech/the-automatic-disconnecting-differential-system-19259.html

If you really want true 2 lo (like I have ) you need a manual tcase with twin sticks to individually control 2wd/4wd, and HI/LO.

 

Nice setup!

Hmmm, I'd say if the front diff was an open type (like 3rd gens are) the power going to the front axle in your scenario above would just spin the disconnected side of the diff since it presents no "load". In any case, that wouldn't give me a warm and fuzzy.