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Gonzo said:
I ask because as I mention before.... what happens if you are on dry pavement and take a hard turn (not that I do), there is some wheel slippage. Knowing how week the system is I get concerned, so coming out of the turn I take my foot off the gas (not what I really want to do) just to stop "any slippage" on the dry pavement.

What do you think? I guess I should simply slow down on this one turn I hit almost every day.
If it is dry pavement, any wheel slippage when cornering is probably because you are going too fast already, not because the tires cannot grip to accelerate the car. In that case, it would be unrelated to the AWD system.
 

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Gonzo-

If you are taking a sharp turn under power and the inside front tire loses traction and spins then the AWD system will engage the rear wheels to compensate for the lost traction. Once traction is regained the clutch pack will disengage the rear wheels.

The MO does not have a differential between the front and rear drive shafts, and therefore cannot compensate for the different shaft speeds when making a turn, especially a sharp turn. My guess is that this type of activity would be hard on the fragile transfer case.

If it was a rental or lease I would not alter my driving habits. However, if you plan on keeping the Gonzomobile after the powertrain warranty has expired then I would lighten up on that particular turn.

-njjoe


:roadtrip: Here comes Gonzo.... :runaway:
 

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Yea that is what I affraid someone was gonna say.... I have been slowing down on this turn for that reason. Too bad the dash didn't have a light to tell you when its engaging... at least you would know if one had to slow down. :p
 

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Gonzo said:
Yea that is what I affraid someone was gonna say.... I have been slowing down on this turn for that reason. Too bad the dash didn't have a light to tell you when its engaging... at least you would know if one had to slow down. :p
Common Gonzo,
we know'ya....you know better...;)
 

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Gonzo-

I like your idea about the AWD activation light. It would be interesting to know when the rear wheels are called into play.

-njjoe
 

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Keep in mind that the AWD system is only active when you are accelerating, since I would doubt any AWD engagement with your foot off the throttle would push any meaningful torque to a non slipping wheel (well not enough to make a difference anyways). AWD is mainly to help you get going in a straight line, not cornering.

I suppose if you are a racer and accelerate through a turn, then AWD would matter, but we don't exactly have Quattro on the MO.

You'd have to be really cooking it to spin the inside front wheel on a turn! :D Not even sure that would be possible with the torque challenged CVT.
 

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Oh I don't know... its pretty easy to spin the front wheels on wet pavement while turning in any FWD drive car I've had with less than 100 HP.... do you think the MO is that pathetic?
 

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Gonzo said:
Oh I don't know... its pretty easy to spin the front wheels on wet pavement while turning in any FWD drive car I've had with less than 100 HP.... do you think the MO is that pathetic?
Probably because I have AWD and VDC, but even with VDC off, I have never been able to spin the front wheels, except maybe on ice. The CVT really bogs it down when you nail the gas from a standstill. But then the MO is a crossover, not a sports car, so I don't care if it can spin its wheels.
 

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Eric L. said:
AWD is mainly to help you get going in a straight line, not cornering.
Says who? AWD is to help you get additional traction when the primary drive wheels have insufficient traction, regardless of what direction you are traveling in.

There is this intersection where the secondary road is a steep incline with a stop sign at the top of the hill. When the road is even slightly damp it is not uncommon for FWD cars to spin the inside tire when accelerating onto the primary road. This happened to me several times when I had the rental FWD MO. However, my AWD MO handles the same intersection with only a slight initial chirp from the front inside tire. In this particular case the rear wheels are helping push the MO through the turn.

The MO does not have a center differential so the AWD system can not compensate for the different driveshaft speeds when the car is cornering. However, when traction is limited the wheel slippage will prevent the driveline from binding up when cornering.

-njjoe
 

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Eric L. said:


Probably because I have AWD and VDC, but even with VDC off, I have never been able to spin the front wheels, except maybe on ice. The CVT really bogs it down when you nail the gas from a standstill. But then the MO is a crossover, not a sports car, so I don't care if it can spin its wheels.
I'm too chicken to try but I would spin the front tires on my 1989 Pulsar easily.... of course the car was lighter but that only had something like 90 HP. I'm sure you can get the MO to spin..... rev in neutral and drop into D.... purchase new CVT "there that was easy" :p
 

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njjoe said:
Says who? AWD is to help you get additional traction when the primary drive wheels have insufficient traction, regardless of what direction you are traveling in.
I think what Eric meant is exactly what you also indicated in your post. AWD in MO does not transfer power side to side so if you are stuck in a corner where different power is needed for each wheel, the AWD on the MO will not be able to do its job like a true AWD can. However, when you are going straight, it does it fine...
 

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Pull up to the stop point. Turn wheel hard right. Nail it. If you don't get a "chirp" your MO needs a tuneup. :)


Homer
 

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AWD with VDC MO's - you won't get any wheelspin on dry pavement.

As for better traction/handling with a FWD biased AWD such as that found on the MO - AWD only comes into play for HANDLING if you are applying throttle through a turn where FWD would otherwise understeer. Now I don't know too many STREET situations where you can even do that. You'd have to pretty much be flooring it through a corner (now I don't know ANYONE who does that on public streets, even with a sports car) and for your average AWD street car, the tires would lose grip and plow you into the opposite lane before AWD quells the understeer (I'm not even sure a full 50/50 split can do that).

Now if we were talking about the RWD biased AWD such as on the G35x or FX, thats a different story! :D
 

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hfelknor said:
Pull up to the stop point. Turn wheel hard right. Nail it. If you don't get a "chirp" your MO needs a tuneup. :)


Homer
Homer,
it does not have to be right, I can do it with wheels left! And not just chirp, Murano will actually spin the wheels easily! :D :D

OK, I have FWD, no traction control....;) except my foot...:D
 

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There can be wheel slippage on dry pavement

I just purchased a new Murano in December with AWD and VDC and within the first week of owning it, i had the scary experience of the front wheels skidding out on me. Yeah, i didn't know the road and the turn was tight and i was probably going a little too fast around that uphill turn but i thought that both the AWD and VDC failed me..
 

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AWD will not help you in a turn unless throttle oversteer is what you want. The VDC in the MO kicks in pretty late - I find that when driving in the snow I always correct the slide before VDC even engages.
 

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The electronic clutch which engages drive to the rear tires acts as the center differential. Since the amount of lockup is variable in auto mode, this allows for differing amounts of rotation between the front and rear.

I think there's maybe a bit of confusion about torque splits in AWD lock mode. If the system is truly locking then torque split no longer has any meaning; it's dynamic depending on the resistance felt at the tires. Full locking means torque split can go from 0/100 to 100/0.
 

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It's not full locking. It uses a clutch, which can (theoretically) slip regardless of the amount of pressure applied.
 

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TC-

Ray is correct.

In normal operation the AWD clutch pack (just ahead of the rear differential) varies it's engagement from 0 to 100%, which equates to a torque split of 0 to 50% between the front and rear wheels.

When the AWD Lock is engaged the clutch pack is solidly locked and the split is maintained at 50%.

A well-designed multi-plate clutch will not slip when fully engaged. Just look at a motorcycle set-up.

-njjoe
 

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MR. Z said it

" the AWD on the MO will not be able to do its job like a true AWD can." ie it works poorly, Or is that cheaply? IMO
 
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