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My Questions is when does it come on, at what tempreture if any and how do i know all 4 wheels are engageing compared to 2. What is the max speed to drive on 4wd lock also?
 

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The 4wd is not Temperature dependent. It takes reading from various sensors - speed, acceleration, "G", wheel slippage etc to determin how much torque is applied through the rear electronic clutch and thereforeto the rear wheels.
To check if it works - try putting the car on a grassy field and trying to drive with and without auto 4wd.
 

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what do you mean by "G", and i was told wit the xtrail we should go above a a certian speed on 4wd-auto and 4wd-lock. is it true
 

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g-force (also G-force, g-load) is a measurement of an object's acceleration expressed in gs. It is proportional to the reaction force that an object experiences as a result of this acceleration—or, more correctly, as a result of the net effect of this acceleration and the acceleration imparted by natural gravity. G-force is not, however, an absolute measurement of force and the term is considered a misnomer by some.

The g (pronounced /ˈdʒiː/) is a non-SI unit equal to the nominal acceleration of gravity on Earth at sea level (standard gravity), which is defined as 9.80665 m/s2 (32.174 ft/s2). The symbol g is properly written both lowercase and italic to distinguish it from the symbol G, the gravitational constant and g, the symbol for gram, a unit of mass, which is not italicized.

The unit g is sometimes written as "gee", and g-forces are informally referred to as "gees" (as in expressions such as "pulling ten gees")


I assume that by "i was told wit the xtrail we should go above a a certian speed on 4wd-auto and 4wd-lock", you actually mean "i was told wit the xtrail we should NOT go above a a certian speed on 4wd-auto and 4wd-lock".

The whole purpose of 4wd is to give traction on slippery and unsecure ground, and by default you should not be going fast. Anyone who wants to do 80 on ice and mud is either suicidal or just plain dumb. I am not sure of the quoted figures by Nissan, but I would suggest that 20mph (30KPH) is more than fast enough. Apart from that, if you use it in fixed 4WD, on non-slippery surfaces (Ie Tarmac) you are likely to screw your complete drive train. Not a good idea:(.
 

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I have seen somewhere the max speed you should go with the 'lock' mode on is 15-20mph, but saying that the owner of my local stealers took it out with me once to try and simulate what causes a fault and on smooth tarmac roads went over 40, when i questioned this, he said it wasn't a problema nd would act like a 4x4 that is in constant lock.

Saying that, like the mad hat man said, the lock is there for difficult conditions and if u can be going any faster than 20 with it on, even if it doesn't cause a problem, there is no benefit, you are just wasting fuel and putting extra wear on other componets-tyres at least for a start
 

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when i questioned this, he said it wasn't a problem and would act like a 4x4 that is in constant lock.

I dont know of any 4x4's that are in "constant lock" - some landrovers have permanent 4WD, but the front and rear driveshafts are not "locked" together. They have a seperate diflock to do that - and if you run it for long in that condition, you risk screwing the drive train completely :(.
 

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sorry i meant permanent 4x4, the 'illness' means my brain doesn't work!

i really have no idea regarding the mechanics of it, can just say what i have been told, but tbh, i don't use that stealers anymore, so it shows that the bond of trust has been warn down. I think its a really a question of common sense, there are few occasions when you need the lock on, and whilst travelling at speed is not one.
 

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Hi everyone. I'm not trying to hijack this thread, but my question is related to the 4WD in a 2006 as well. My understanding of the 4WD in an X-Trail is this;

2WD = Front wheel drive only.
AUTO = 4WD only when the X-Trail sensors deems it necessary.
LOCK = Constant 4WD

Question 1) Is this not correct?

Question 2) I leave my X-Trail in AUTO mode 90% of the time and the green 4WD dashlight never turns off. Is this normal?

Question 3) In my old Jeep I would often switch to 4WD HI and do 80 KPH through the snow. 80 KPH was the manufacturer specification. Are you telling me it is not recommended to drive faster than 40KPH using AUTO/LOCK?
 

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Mad Hat Man are you telling me you have never driven your X-Trail in AUTO over 40KPH? I find that very hard to believe.

So is LOCK like 4WD LO? With my old Jeep 40KPH in LO really rev'd the crap out of the engine. It was meant for high torque stuff, like pulling boats out of water or heavy 4x4'ing (which I did very often - seriously).

As far as AUTO goes, there is no speed restriction. I should be able to pin the speedometer out, not that I would.
 

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Mad Hat Man are you telling me you have never driven your X-Trail in AUTO over 40KPH? I find that very hard to believe. I rarely use auto on tarmac, except in exceptional conditions.
So is LOCK like 4WD LO? With my old Jeep 40KPH in LO really rev'd the crap out of the engine. It was meant for high torque stuff, like pulling boats out of water or heavy 4x4'ing (which I did very often - seriously).NO - LOCK just locks the ellectronic diff, so that yu are applying power to all 4 wheels. - there are NO hi and lo ratios on a X-T.
As far as AUTO goes, there is no speed restriction. I should be able to pin the speedometer out, not that I would. Thats because it only operates when necessary (wheel slip) and yu are unlikely to get wheel slip at 100KPH and the max cut-in speed may be electronically governed.
Now I may well be wrong, but I always consider 4wd is for use on suspect road surfaces and I still maintain anyone driving on gravel, mud or sand at high speeds in an X-T has a death wish.

I have now had more time to consult the Nissan manual and I show certain passages....

firstly the basic design of the 4wd system. Note fully electronically controlled.


Next the electronic control - note input from many sensors.




Auto mode


Lock mode


As can be seen, the Nissan system is fairly fool proof.
If the system is left in Auto mode, it will not enable drive to the rear wheels unless neccessary.
If the system is left in LOCK mode, it will revert to Auto mode over a certain speed and again, will not enable drive to the rear unless necessary.
At least it is now confirmed that by leaving it in AUTO or LOCK, it will not wind up the transmission as it just wont be enabled.

To repeat my point 4WD on tarmac'd roads is unnecessary and, reading the manual if the car is left in AUTO or LOCK, unlikely to have any effect. Please remember this isnt an Audi Quattro or Golf R32 we are talking about here - its a brick on wheels.
The car is not designed to perform in an African Rally - It is designed as a "Chelsea tractor" with occasional light off roading. If you want to go tree felling in Siberia, you wouldnt want an X-T - more a minimog. Albeit that the X-T isnt a bad little off roader how many armed forces use one as their "go anywhere" vehicle.
 

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Wow! Awesome post Mad Hat. A ton of information in there. Much appreciated. I think I will email Nissan for more details. I find the description of LOCK a little vague. "If the vehicle speed increases". Does this mean if I'm in LOCK and I increase my speed from 15KPH to 16KPH LOCK disengages? It is probably more like 20KPH to 30KPH, but it would be nice to have a number.

It is nice to know the system is fool proof. I didn't want to be worried about switching to AUTO and ending up on LOCK because my mitts were too bulky to tell the difference.

I agree with all your points about the X-Trail's 4WD capabilities except for one. The X-Trail is more like driving a refridgerator on wheels. My old Jeep was definitely the brick.

Thanks again for the post.
 

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I find the description of LOCK a little vague. "If the vehicle speed increases". Does this mean if I'm in LOCK and I increase my speed from 15KPH to 16KPH LOCK disengages? It is probably more like 20KPH to 30KPH, but it would be nice to have a number. I dont think it matters - what it states is that the system will change automatically from LOCK to AUTO when the sensors decide that it is unnecessary to have a locked system, but will return to LOCK when the speed is slow enough for it to be safe to do so. As it is sensor dependant, maybe the changeover speed depends on several factors and isnt fixed?
It is nice to know the system is fool proof. I didn't want to be worried about switching to AUTO and ending up on LOCK because my mitts were too bulky to tell the difference. It doesnt seem to matter - as you speed up, the system will automatically change from LOCK to AUTO for you.
I agree with all your points about the X-Trail's 4WD capabilities except for one. The X-Trail is more like driving a refridgerator on wheels. My old Jeep was definitely the brick. - NO - a refrigerator is driving a Land rover Series 3 with no heater, carpets?? in the winter.

The X_T aint a refridgerator - the air con on mine works fine :D
 

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Wow! Awesome post Mad Hat. A ton of information in there. Much appreciated. I think I will email Nissan for more details. I find the description of LOCK a little vague. "If the vehicle speed increases". Does this mean if I'm in LOCK and I increase my speed from 15KPH to 16KPH LOCK disengages? It is probably more like 20KPH to 30KPH, but it would be nice to have a number.

It is nice to know the system is fool proof. I didn't want to be worried about switching to AUTO and ending up on LOCK because my mitts were too bulky to tell the difference.

I agree with all your points about the X-Trail's 4WD capabilities except for one. The X-Trail is more like driving a refridgerator on wheels. My old Jeep was definitely the brick.

Thanks again for the post.
Hi there,i ve tried to switch from AUTO to 4WD in speeds above 80km/h on snowy roads and barely saw a difference the huge difference was when i switched from 4WD to 2WD again at speeds over 80km/h the reaction was like driving a normal car.The front of the x-t going from left to right made me put back to 4WD,much stable .I drive in remote roads where the snow plow doesn t go often and when my wife is not confident with road conditions she puts on 4WD at speeds over 100km/h with the engine cruising in overdrive.:)
 

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Doing 60KPH+ in 4WD must be a Canadian thing. :)
Our Ski Team was often referred to as "The Crazy Canucks" :)

I'm no expert on this subject but will offer some thoughts from my own experience....

2WD is self-explanatory (and it is the front 2).

4WD "AUTO" is till 2WD (front only) UNTIL the sensors detect some slippage - - then power is transferred in a proportional way between both the front & rear wheels.....

Once the slippage has been overcome it reverts to 2WD (front) even though the button is in the 4WD AUTO position.

With it in 4WD "AUTO" mode, you can effectively drive any speed you want (or is legal) because only the front wheels are active UNTIL there is slippage.

In 4WD "LOCK" both front and rear wheels are engaged. The intention (as I understand it) is to give that extra "grip" to get you out of a mud-hole - snow-bank, etc. etc.

4WD "LOCK" is NOT INTENDED for any significant driving. It's just to get you "unstuck" or enable you to traverse an area at a limited (slower) speed.

As I further understand it, there is a "fail-safe" design built in (to protect various components) that "disengages" the 4WD "LOCK" at 50 kph or above.

It then reverts to "AUTO" mode.

In the winter months, I have mine in "AUTO" most of the time and when on the highway do speeds between 90 & 120 kph, depending on road conditions.

Don't know if this brings clarity or more confusion :confused: but thought I'd give it a go.

Cheers = Roger
 

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As far east points out - this is correct and how I was told when I got my bonavista.

lock to get u out of the heavy stuff (lots of snow/mud) and auto for most everyday winter driving. We turn it it 2 during the summer and only auto during a freak rainstorm.

its not like a low/high range thing as in a real 4x4.

I'm in montreal and with proper winter tires, I haven't been stuck once!

She just loves the white stuff....ice though, thats another story!
 

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