Full time 4wd (1 Viewer)

[Eddyeight]

Again, another dumb question from me. Searched some threads, but I want to make sure real quick. Drove my Land Cruiser down to Bama yesterday and I averaged about 14 mpg. This normal? Also, I realized that all tires were spinning when I took it on a local trail, but I had nothing engaged. This thing is full time 4WD, right? If so, sweet...just making sure.

Oh, it's a 98 model btw....Happy Thanksgiving to everyone.

 

[Campfire]

Yep! It's full time 4WD.
There is a conversion out there to make it part time, but $$ if you're not worried about it.

 

[pman]

Technically its AWD unless, you press the CDL button on the dash. Why on earth would you pay money to make it part time 4?? I love the fact that cruiser are full time 4

 

[spressomon]

Again, another dumb question from me. Searched some threads, but I want to make sure real quick. Drove my Land Cruiser down to Bama yesterday and I averaged about 14 mpg. This normal? Also, I realized that all tires were spinning when I took it on a local trail, but I had nothing engaged. This thing is full time 4WD, right? If so, sweet...just making sure.

This vehicle is very happy at 2,000-2,200 rpm for highway cruising. That is the 4.7L's sweet spot on this rig. So if you keep the rpms down you will see improved fuel mileage...and visa versa .

 

[SALEH]

i replace my transfer case to Land Cruiser Part time 4WD Drive

 

[KingBeeIII]

i replace my transfer case to Land Cruiser Part time 4WD Drive

And have you experienced any bennifits from that?

 

[ShottsUZJ100]

Technically its AWD unless, you press the CDL button on the dash.

Technically, nope.

AWD = Normally power goes to one axle (2WD) until slipping is sensed. Then the power is temporarily sent to the other axle as well. When slippage ends then you're back to one axle (2WD) power. Also...AWD models rarely have a 2-speed transfer case.

Land Cruiser = Permanent Four Wheel Drive = Power is going to both axles all the time and cannot be disengaged to a 2WD mode. If you could disengage the LC to a 2WD mode then you have a "Selectable 4WD vehicle".

All the CDL does in the LC is lock the power equaly to both axles.

 

[EdsCruisin]

Technically, nope.

AWD = Normally power goes to one axle (2WD) until slipping is sensed. Then the power is temporarily sent to the other axle as well. When slippage ends then you're back to one axle (2WD) power. Also...AWD models rarely have a 2-speed transfer case.

Land Cruiser = Permanent Four Wheel Drive = Power is going to both axles all the time and cannot be disengaged to a 2WD mode. If you could disengage the LC to a 2WD mode then you have a "Selectable 4WD vehicle".

All the CDL does in the LC is lock the power equaly to both axles.

So, what are the typical percentages of power to each axle when on dry, stable pavement? Even my other AWD vehicles were still running 90/10 in good conditions. As I understood it, the LC system is more or less a limited-slip transfer case, like the Jeep Quadratrac - transferring power to the non-loose end of the vehicle.

 

[ShottsUZJ100]

So, what are the typical percentages of power to each axle when on dry, stable pavement? Even my other AWD vehicles were still running 90/10 in good conditions. As I understood it, the LC system is more or less a limited-slip transfer case, like the Jeep Quadratrac - transferring power to the non-loose end of the vehicle.

Ahhhh....I don't remember the "typical" power ratio though I seem to remember it was closer to 50/50 on the 100-series. I want to say something like 60/40 or 70/30? Don't recall.

Most AWD vehicle sends 100% power to one axle until it detects slippage.

 

[BManning`]

I had a Subaru Forester years ago and I remember that the AWD system would change power distribution during cornering & acceleration to "optimize" traction. In other words, it didn't wait for slip, it was a proactive system.

Does the LC t-case do this, or would it wait for slip to change the power split?

Also, anyone care to discuss the difference between viscous and non-viscous t-case operation? IIRC 100's aren't viscous, but I think 200s are.

Just curious, since it's on-topic...

 

[ShottsUZJ100]

I had a Subaru Forester years ago and I remember that the AWD system would change power distribution during cornering & acceleration to "optimize" traction. In other words, it didn't wait for slip, it was a proactive system.

Does the LC t-case do this, or would it wait for slip to change the power split?

Also, anyone care to discuss the difference between viscous and non-viscous t-case operation? IIRC 100's aren't viscous, but I think 200s are.

Just curious, since it's on-topic...

I corrected my last post. I should have said "most".

100 and 200 are open center diffs. 80's had VC's.

 

[BMWSTOY]

With the snow we received and icy roads, I sure was able to get mine to go BEEP, BEEP, BEEP today - pretty fun sliding in a full time 4X.

Yahoo

 

[96r50]

100 and 200 are open center diffs. 80's had VC's.

I don't know about the 100 (although I believe it to be the same), but the 200 has a Torsen limited slip, not an open centre differential. So does the manual transmission FJC, fulltime 4WD 4Runner and the Lexus GX470.

 

[ShottsUZJ100]

I don't know about the 100 (although I believe it to be the same), but the 200 has a Torsen limited slip, not an open centre differential. So does the manual transmission FJC, fulltime 4WD 4Runner and the Lexus GX470.

Yep! Brain fart! Sorry!

 

[BManning`]

Again since it's on subject...

...What's the difference between how the 100's t/case operates vs. the Torsen setup used in a lot of other Toyotas?

Is the Torsen setup more efficient, which would explain why it's used so often in other models & 200s?

 

[Trunk Monkey]

Just guessing here since I at one time assumed the 100 t-case was like the 80's with a viscous coupler. Since the 100 t-case is "open" it will send power to the axle that slips. A t-case with a torsen type diff in it will send power to the other axle when one begins to slip. Locking the center diff in the t-case splits the power 50/50, no possible other split.

 

[Waggoner5]

My 07 was an open center, now 2wd.

 

[ShottsUZJ100]

Just guessing here since I at one time assumed the 100 t-case was like the 80's with a viscous coupler. Since the 100 t-case is "open" it will send power to the axle that slips. A t-case with a torsen type diff in it will send power to the other axle when one begins to slip. Locking the center diff in the t-case splits the power 50/50, no possible other split.

Thank you for triggering my memory.

The 100's center diff is open. It'll send power to one axle or the other or both. Then the diff can be locked which doesn't permit slippage.

The Torsen diff can vary the power percentage between the axles biasing the power where it's needed. It's an improved system when needing an un-locked full-turning capability ride.

 

[Letsgomoreplaces]

differential

The US model 100 series all have a standard open differential int the transfercase. The front & rear differentials allow differentiation in wheel speed side to side while cornering. Since the front axles overall arc in a turn is much greater than the rear axle, it is also necessary to have a differential in the center to allow different driveshaft speeds front and rear. The CDL simply locks the center just like the axle differential locks. The FZJ80 tcase uses a viscous coupler, which is kind of like having an LSD but in the center (as does the torsen in the 4runner tcase). I have done plenty of driving in varied conditions with both the viscous coupled 80 or in the 100 and I never saw advantage of the Viscous coupler over open center diff, since you can simply hit the CDL if you did need additional traction in high range.

 

[BManning`]

The US model 100 series all have a standard open differential int the transfercase. The front & rear differentials allow differentiation in wheel speed side to side while cornering. Since the front axles overall arc in a turn is much greater than the rear axle, it is also necessary to have a differential in the center to allow different driveshaft speeds front and rear. The CDL simply locks the center just like the axle differential locks. The FZJ80 tcase uses a viscous coupler, which is kind of like having an LSD but in the center (as does the torsen in the 4runner tcase). I have done plenty of driving in varied conditions with both the viscous coupled 80 or in the 100 and I never saw advantage of the Viscous coupler over open center diff, since you can simply hit the CDL if you did need additional traction in high range.

Great post & thanks...clears it up for me...