Recently I found myself in quite of a bind. I planted myself in the "V" shaped bed of a wash, that ran down hill at a 45 Deg Angle, running perpendicular to the edge of a deep and rocky ravine. Sure, wouldn't normally have been a problem but the X leaned dramatically to its left. With a little pressure on the gas, only the higher side's rear tire spun.
You see, the odd thing was that I was in 4 Lo and only one tire was spinning. Someone said: "Well, maybe your 4X4 hadn't locked yet before you gave up on hitting the gas...." No, sorry, I was trying to free it for a while, Still no other tires budged. However, the 4X4 was fully functional right after digging myself out with a tiny-ass shovel.....
So, guys, what the hell is up with the Xterra's 4 Wheel Drive ability?

Were you in 4Lo before hitting this and all hubs were locked? As for the tire spinning freely, then that means you have an Open Diff, like some of us do. Basically, all of the engine's torque is going the path of least resistance, the free wheel. With an LSD, that torque is split between the two wheels, unfortunately, it's usually not enough to get you unstuck. The only REAL solution is a Locking Diff. It locks both the left and right wheels, and they receive the same amount of engine power. To learn more, take a look around and search for LSD and Locker.

Nothing's wrong with it.
Your rear tire with little traction will spin, limited slip or not. You need a locker if you want power to the wheel with more traction.

As for why neither wheel up front was turning, I don't know. Bad hubs, hubs not fully engaged, transfer case not fully engaged, or something is broken.

Did you do a little backing up to try to get unstuck?

If you back up the auto hubs unlock and you need to roll about 3 ft forward for them to lock back up.
Since you're stuck you can't go forward more than a foot or two and you end up only sending power to the rear axle.

I appreciate the help...
I am aware that locking diffs would solve the problem, but I was trying to stress the concern that the 4 Lo was not functioning at all during the incident, but was fully functional immediately following. I suppose it's just one of those things where you'd have had to have been there. Anyway, that Xterra's sold and we'll see if I can't come to understand what happened...
Thanks though...

It has alot to do with the fact that you had one wheel in the air. That was your major problem.

Bzzzt! Wrong! You don't have to move an inch for the front hubs to re-lock after you change direction. It's a function of the axles rotating, nothing more. The axles are able to rotate within the hubs without the wheels moving at all. If the rear wheels spin, then this happens without you moving an inch.
The problem is that the rear wheel(s) must actually rotate at the same time since there is no center diff. For the front shafts to rotate, the rear shafts must also rotate. This results in only the rear wheels doing work for the (maximum of) 1 rotation of the driveline. On the X with 31" tires, the vehicle would travel about 8 feet assuming it takes a full rotation of the front axle within the hub to complete the dis/re-engagement process (it's probably less) and that the rear tires actually have sufficient traction to move you the entire 8' while the front end isn't helping (in which case, no problem).
If the rear end doesn't have sufficient traction, well, they'll spin one full revolution (or less) in place while the front end re-engages, then you'll be in 4WD again. Problem is the rear wheels may have dug in deeper or slid sidways in the process, and THAT is where the brief dis/re-engagement manifests itself as a problem. Also, if the wheelspin is rapid, the shock placed on the hubs as they re-engage can damage them.

Make sense?
Brent

I don't think any 4x system should unlock itself. I think Nissan should rethink their design.
-Chris

Should Toyota rethink theirs as well since it is virtually the same?

Once my truck is in 4x the sys will never unlock itself.
-Chris

Are you sure you know what you are talking about? If your Toyota has Auto Locking hubs, the same phenomenon can happen to your rig as does with the Xterra. When chainging directions, the Hubs can unlock for a very short amount of time.

Different system on a Tacoma.

The hubs are always locked, it disconnects near the diff.

Ah, so he's lugging around turning all that extra hardware, taking a minor mileage hit, and wearing it all out (or at least requiring more frequent maintenence) faster than we are...

Brent

So if you are stuck in a rut and you rock back and forth to unstuck, you are unlocking hubs, but in a few seconds you lock them again so you are back to using your 4wd? If I understand Brent's post, put up with wheel spin for a few seconds until hubs lock?

A few seconds? More like a second, max. But yes, you will either move with no problem while in 2WD, or you will spin the rear tires briefly, or a little of both.

Brent

if the slight time lapse involved with auto hubs bothers you THAT much, go get a set of warn premium manual hubs. you will KNOW when they are locked because you will have to get out, walk around, lock them, and get back in for you to be in 4wd. I blew an auto hub on my 94 bronco back in the day, and to save money i replaced both hubs with the warns. while they are in a different ballpark where strength is concerned, i thought it a pain in the ass to have to get out and lock them in the rain, mud, snow, whatever. bottom line...learn to predict that you will probably need 4wd when crossing a creekbed, and plan ahead by doing nothing but pulling back that little lever, or get manual hubs, which, unless you need them for the extra strength, you will regret, as auto hubs are strong enough for 95% of what the stock X will be put through, and are a convenience that you will miss once its gone.

my $.02
michael

Originally posted by OffroadX:
>>Ah, so he's lugging around turning all that extra hardware

A lil extra hardware yes.

>>taking a minor mileage hit

Probably small, but not really noticable, I get 16-18mpg normally w/ city and highway, so it's still good. I have hit 23mpg on my best freeway run so far when I went to Moab last summer.

>>wearing it all out .

Nobody from my board has ever worn them out. I mean, there's a lot of items on your truck that spin all the time and don't really wear much like your driveline and rear axles. But even still, I plan on switching over to manual hubs sometime far in the future when I do a long travel front suspension setup.

>> (or at least requiring more frequent >>maintenence) faster than we are...

It's sealed, no maintneance at all. When I switch to manual hubs then I will have to inspect them from time to time.

-Chris

PismoTaco what are you doing on this board ?
if your truck is so much superior and shit , why do you keep comming back here?

I think he needs to put in his Signature TOYOTA

Or even TOYOTA, NOT AN XTERRA

Or EVEN TOYOTA TACOMA

It's like he's trying to hide the fact that he doesn't really belong here. There are others with vehicles other than Xterras, and they don't do this whole "mine's better than your's" crap.

It's annoying.

Not defending him any but I don't think (at least in this thread) he has ever said anything about his Toyota being better. It started with him suggesting Nissan re-think the design. Then someone jumped him saying they were the same when he replied they were not.

Again not defending him but he seems to have a bit a knowledge in off roading skills. And unless Ian really lays the hammer down on non xterra owners registering people will always come here X or otherwise.

I never try nor intend to start any "my truck is better than your's arguments", that's not my style nor would I stand to gain anything from it.

I'd like to think that I have a lot of offroad experience and knowledge, both to share as well as gain. I honestly try and answer questions as best I can. As in this thread, I answer questions w/o putting down other vehicles. I will soon have my BS in Mech Engr and sometimes I can better answer technical questions, or at least make a decent shot at it, but I'm still learning here and there.

I'd like to think I have made very worthy contrabutions to many threads even though I'm only rated 3of5X's. I really wish I could get a higher rating, but sometimes think owning a taco hurts me, maybe not, never the less, I try to be patient.

I'm always looking for the new ideas and the best design; it may be nissan, toyota, or ford, but to be brand loyal blind would only hurt more than it would help. I havn't included my sig on this board becasue this board has seemed less open/welcoming than other boards.

I'd also like to say that I have already been on a NorCal X run and througly enjoyed myself; I got to have fun wheeling as well as meet a bunch of great people.
-Chris

I can vouch for Pismo being a nice guy - I don't think he was ever suggesting that his truck is better than an X. I think we can all agree that were we asked to say what we wanted in our "perfect" truck, there are probably some things we would change...

Also, Pismo's not a baby about using his truck - while not being overly reckless. True, he went up one of the tougher hills in REVERSE, but on that day the hill really wasn't "all that"... I think we all enjoyed having him join us that day.

He seems a lot more intelligent and more of a gentleman than njcruiser.

Thanks to David, GrumpyTom, XMan6, and any others I may have missed. Your support is well appriciated.
-Chris

Manual hubs can solve all this! They are engaged when you turn them and stay there until you either grenade them or turn them out. And rarely do they grenade (warn anyway)
Rock on!

I would have to agree with the manual hubs being a better choice for the more serious off roading situations. As for them being a pain in the butt I think of them as a minor inconvenience. If you know that you are going to get into someplace where you will need 4X4, it will take you about 30 seconds to get out and turn your hubs in. Even less time if you have your passenger do the other one. True while the hubs are locked you will be turning the front diff but that should not put excessive wear on it, especially if you still have the stock open diff, and you will still be in 2WD untill you pull back on the T-case lever. Just my 2 cents worth but I like the solid feeling of having manual hubs and a transfer that you can "feel" lock into place rather than just pushing a button or turning a knob and hoping that it's in 4WD.