TOD and no rear driveshaft....

[Marlin]

Well, I promised I would try the VX with no drive shaft. 4Hi=no good. TOD is not fast enough, and it seems to constantly read the rear "slipping" and it momentarily sends power to the front and then starts over again. Its ends up being a jerky stop and go. This is why I am not a big fan of TOD, and this experiment proved that its not a great thing for snow/ice. That pulsing power transfer sounds like a recipe for disaster.

4low was fine, except I am locked, so it was a bit messy as far as steering and shifting. I would not drive it around town like that, but I would guess on the trail it would be fine, say for a busted drive shaft or universal or whatnot.

[Triathlete]

As punnie as the front drive shaft is, i would drive gingerly in that mode or you may be replacing that one also.

[atilla_the_fun]

If one had manual hubs in the front, could one disconnect one of the two wheels and drive in 4L, with the driveshaft disconnected as well? 1 wheel drive?

[Marlin]

If one had manual hubs in the front, could one disconnect one of the two wheels and drive in 4L, with the driveshaft disconnected as well? 1 wheel drive?

Only if you had a locker. With out OEMopen diff, you only get as much torque to the wheels as one needing the lowest amount to turn, which would be the disengaged hub. The diff would see that wheel as still spinning. Now with a front locker.....I don't even want to imagine how horrible that would be. It would be bad on the drivetrain, unbalanced stress on shafts and whatnot.

As for snow driving, I have read many complaints on here about TOD in the snow causing problems. Based on my experiment with the driveshaft. There was definitely surging and pulsing of power to the front, I could see it on the TOD display as well. That means, if I had a little traction in the front, then a surge in power, I just lost what little I had going for me in the form of spinning tires.

No worries, if it works for you, thats awesome, I just don't know that computers and technology in an Isuzu were really fast enough to make for seamless TOD ops in slippery conditions. I can tell you it sucks with no drive shaft and it sucks on gravel.

[blacksambo]

Not so quick, Mr. deep south. We have two '99's that out perform everything else in the snow and ice. I have never felt anything so sure footed in slippery surface conditions. We drive 'em everyday through you name it, and they operate flawlessly. If something else could do the job we'd be driving it, it doesn't exist. Move here and then try your experiment? You'll be whistling a different tune. Those Russian Vx'ers know what I'm talking about.

[Ebenezr]

I may be needing a transfer case soon and i have noticed some of the same time period troopers had a 4 hi option. I have found them in used parts locaters. I'm considering placing one in my vx. They are otherwise identical to our T-cases.

[Marlin]

I may be needing a transfer case soon and i have noticed some of the same time period troopers had a 4 hi option. I have found them in used parts locaters. I'm considering placing one in my vx. They are otherwise identical to our T-cases.

Well, they will fit, but they may be different. I believe the drive shaft flange may be different. I am not 100% for sure, but I would check first. If it is, should just be a matter of taking the fitting off of your case and swapping it over.

I do know the non-tod case will fit in ours, but definitely has a different prop shaft flange. I would personally go the non TOD route in order to gain a 2hi option. You would have to get the stick as well, but no biggie.

[Ebenezr]

I'm thinking its has all 3 TOD, 4hi, 4lo. Actually I just looked thru the manual and it appears this is wrong. If you want 4hi you give up TOD....

[Ldub]

I'm thinking its has all 3 TOD, 4hi, 4lo. Actually I just looked thru the manual and it appears this is wrong. If you want 4hi you give up TOD....

I'm reasonably sure, after a few conversations on the stoop in Moab, that you would also need the computer & frt axle from the donor Trooper.
The Troop frt axle is vacuum controlled, which would also need to be addressed...http://www.4x4wire.com/isuzu/tech/fwd_lockout/?

[Ebenezr]

I'm reasonably sure, after a few conversations on the stoop in Moab, that you would also need the computer & frt axle from the donor Trooper.
The Troop frt axle is vacuum controlled, which would also need to be addressed...http://www.4x4wire.com/isuzu/tech/fwd_lockout/?

I don't understand the vacuum actuator mechanism but I did look at the Trooper info in the manual and there is a 4 bolt flange coming out of the front pumpkin to connect to a more robust front drive shaft. If TOD is present on the Trooper then it has a round 6 bolt flange to connect to the limp wristed Front TOD shaft. At least the length of Trooper and VX front shafts are identical 22.7 inches. So I'm with Chris - the next move may be a 4 hi transfer case with no TOD wiring!!!

[Ldub]

I don't understand the vacuum actuator mechanism

I believe it's for the shift on the fly function.

[Marlin]

I'm thinking its has all 3 TOD, 4hi, 4lo. Actually I just looked thru the manual and it appears this is wrong. If you want 4hi you give up TOD....

That is a bad thing? This would allow you to have 2hi, 4hi, 4low, like our JDM cousins. Less electronics is a good thing, especially as our vehicles get older. The less wires, the more reliable

[Triathlete]

After thinking a bit I have come to the conclusion that your front drive only experiment means moot. And here is why...
When in 4hi the front end was getting 20% power...obvouosly not enough to pull the VX. All wheels would have been turning equally at the same rate.
In 4lo there should not be any jerking since in 4lo the transfer case is mechanically split 50/50 and takes TOD out of the equation.

[Marlin]

After thinking a bit I have come to the conclusion that your front drive only experiment means moot. And here is why...
When in 4hi the front end was getting 20% power...obvouosly not enough to pull the VX. All wheels would have been turning equally at the same rate.
In 4lo there should not be any jerking since in 4lo the transfer case is mechanically split 50/50 and takes TOD out of the equation.

I agree, except that its not moot. TOD should sense the rear wheels slipping (no drive shaft, the puter thinks it is, so it senses slipping, no different than it would be on snow) and subsequently sends power to the front. That was the problem, it doesn't take the slipping input and then transfer power at a rate fast enough to make it doable,hence the jerky responses, then it seemed to reset and start the process over, giving it that bouncy jerky effect. Having said that, imagine the effects of the delay on snow or ice.

If I had to drive this way, it would be in 4low only, to remove TOD from the picture and have the straight mechanical drive engaged.

[Triathlete]

I agree, except that its not moot. TOD should sense the rear wheels slipping (no drive shaft, the puter thinks it is, so it senses slipping, no different than it would be on snow) and subsequently sends power to the front. That was the problem, it doesn't take the slipping input and then transfer power at a rate fast enough to make it doable,hence the jerky responses, then it seemed to reset and start the process over, giving it that bouncy jerky effect. Having said that, imagine the effects of the delay on snow or ice.

If I had to drive this way, it would be in 4low only, to remove TOD from the picture and have the straight mechanical drive engaged.

Where does the tod computer get its wheel speed input from? Maybe I am missing something but, if the VX is moving, with or without a driveshaft all four tires are spinning at the same rate so why would the tod send power to the front? Sounds like it is doing what it is supposed to.