uHu said:
Great advice though me not want CDL on especially downhill and icy. CDL on the suspension can settle especially turning.
Center Diff Lock - Educate me please
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Great advice though me not want CDL on especially downhill and icy. CDL on the suspension can settle especially turning.
uHu said:
Just like a F or R locker can cause sliding and wheels to scuff and driveline to settle, so can a CDL especially when turning. On ice, I want everything open whenever possible. This way the driveline will not work against me.
ShottsUZJ100 said:
Yes. Me agree. But,
on ice/snow, the wheels will always skid and slip a bit. More than what is "forced upon them" by the CDL during normal driving. I would say CDL off only when moving slowly in a tight space when the steering is turned more than half-way towards max. This is on ice or wet snow.
BTW there was a test of 4wd-systems some years ago, where the conclusion was that on snowy roads, it was easier to drive, or faster, with part time systems with 4wd engaged (meaning no CD) than on more advanced systems with full time 4wd with no lock on the CD.
uHu said:
My results are based on my truck only. The UZJ100's traction control is extremely well controlled. Forward progress is kept in control with TRAC and VSC. Locking the CDL turns off the Vehicle Skid Control.
On a non-UZJ or non-TRAC controlled rig....I could be dead wrong.
uHu said:
Oh, you have an HDJ.....no TRAC or VSC.....correct?
uHu said:Correct.
(it's DIY TRAC & VSC)
Then I'll bet you're correct (exceot for the UZJ). I always take the 100 to those conditions, not the 80s.
Good discussion, with my FZJ80 I found that if it was heavy snow 12-18" going up the very steep hill to my house that curved to the right half way up that I was better off with unlocked and more speed. If I locked it would slide off the road when the road curved. I am sure my 99 would do the samething. I like the down hill decent control on my 2004 4runner. It would walk me down that same hill in the morning with no problem. This was a bad hill and I normally did not want to take the FZJ80 back down until it cleared some. I tried it down several times with the 80 and I found that unlocked using ABS going very slow worked best not great, (sure the 99 LC would be the same deal).
SWUtah said:
Excellent. This is another example of why I always recommend a 2000+ Cruiser to my friends. You get the electronic safety goodies and you can add lockers.
I've carefully reviewed this forum after my experience on driving in the rare but heavy ice we've gotten in AR. I've found that LOW cannot be engaged without also engaging the CDL in my '99 LC. Is this correct?
Btw, I am very impressed, as I have had this vehicle for a year but never the chance to drive it on terrible conditions like now.
After studying the manual and the forums ever since I got the ride, tonight I realized that I really didn't know as much about the Rear Locker and CDL as much as I thought I did while on the road.
Btw, I am very impressed, as I have had this vehicle for a year but never the chance to drive it on terrible conditions like now.
After studying the manual and the forums ever since I got the ride, tonight I realized that I really didn't know as much about the Rear Locker and CDL as much as I thought I did while on the road.
uHu said:
Could you post a link or other to that test report/article?
I'm wondering what the "more advanced" systems were - various viscous type couplings, some with electronic controls of the slip, electronically-engaged locking, etc. ?
I've seen info showing that the various "more advanced" viscous coupling and/or electronically controlled center slip/lock systems do indeed underperform, because there is always a lag between (a) slippage starting and (b) the system response. (And the system response may not be adequate, even once it actuates.)
One article in particular several years ago sticks in my mind - talking about the (then new) Mercedes SUV thing built in Vance Alabama, and how its "advanced" AWD system failed miserably on ice, freaking out and oscillating the power distribution wildly with spastic braking also, as the system was unable to deal with the icy conditions. (The author noted that plain part time 4WD vehicles passed him easily as his "superior" Mercedes floundered, their drivers smirking at him on the way past.)
Contrast this with the normal mode full time 4WD of the 100: Always fully enaged, approx. 50/50 front/rear, no response lag, no wishy/washy oscillation of power distribution, no fancy braking dance outside of driver control (1999 model).
Sure, the floating center diff may allow unwanted FR or RR spin if put into extreme conditions. But my own experience with it in snow & ice is, that due to the smooth ~50/50 split at all times, in most situations it simply pulls right through the mix without even blinking an eye.
I'm not a hardcore offroader, but IMO, the 100's simple center diff with optional lock is the way to go. No complicated electronics & control systems, no response lag or goofy response, always engaged ~50/50. Simple. Durable. (K.I.S.S.) Transparent to the driver under most circumstances (except extreme off-road). I think its superior to the various part time 4WD/AWD systems with variable couplings & fancy control electronics, and superior also to the all-or-nothing of simple part time 4WD without center diff (which cannot be used on mixed high-traction / slippery conditions.)
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Tinkerer said:
You mention a 1999 model year? Just note that a 98-99 100-series takes a big step back in these slippery conditions to a 2000+ model year due to A-TRAC and VSC. No comparison in capability.
ShottsUZJ100 said:
Yeah, there's always something better like TRAC coming out with the next model year...or is there?
" If TRAC kicks in AND for some reason you need to BRAKE, the breaking does not kick in as TRAC has the priority."
Is that true? I'm not sure I would want TRAC, if so.
I wouldn't want to have to engage the center diff lock to maintain my right foot priority over the brakes - what about unplanned slippery conditions that happen without warning, so I forget to lock the center diff or don't have time to lock it? TRAC may override my braking? No thanks!
I contend that a skilled driver without ABS and traction control can do as good or better than a "B" driver with ABS and traction control. Just my own opinion.
But man, the braking override by TRAC is scary. Wow. Good luck with that.
Tinkerer said:
If you have TRAC you'll never go back to a non-TRAC setup. It's seamless and offers too many advantages. You not need to lock you CDL for TRAC to work properly EXCEPT in off-road situations (where you'd want the CDL locked anyways). Brakes will take priority in all "normal" situations.
Gohawks63 said:
From experience...absolutely NOT true. When cross-axled off road with the CDL UNlocked, TRAC can have priority for a few seconds even with the brake pedal pressed. This is dangerous and can lead to a loss of control...like rolling back down a hill.
We're not talking forest roads and mild wheeling or ever on-road. This will only happen if severely flexed out and the CDL is open.
Off-road trail driving = LOCKED CDL
Well, this test was done MANY years ago by the leading Auto-magazines of the Nordic contries (Norway, Sweden and Finland, at least), on snowy winter roads. Partly deep snow (for beeing a public road). Don't think the report is available on the net. What I remember is the conclusion, that the Toyota Tercel Wagon 4WD, with the simplest system in the test, and maybe cheapest to, came out best in stability, handling, acceleration and maybe braking. The cars where small family cars, and some were more than twice the cost of the Tercel. The basis for the success of the simple 4wd system (locked or no CD) is that the front and rear axles are forced to move at the same speed, which is an advantage when going more or less straight on slippery surfaces.Tinkerer said: