Slow to release four wheel drive in D40

[acko13]

OK...I have had my D40 STX manual for a couple of months now. Last weekend I took it down the beach to the Murray Mouth. In both high and low range 4WD the car performed very well with the tyres dropped to 20 psi ( the sand was damp and not all that difficult).
When I got back to the car park and re inflated the tyres, I put the car into two wheel high, but it would not come out of 4WD. I drove it forward and back a few rtimes...no change. Hmmmm...OK I drove it rather vigourously in reverse and then forwards. Aha! That did it. Now is this normal with this model? Or is it just that the vehicle is fairly new?

 

[Old.Tony]

Being an electronically-controlled transfer case, my guess is the sensors hadn't determined that it was "safe" to release 4WD mode immediately.

I can't say I've ever had the problem but I've never been on beach sand - I've done some river crossings, driven through sand on forest fire trails and played in LOTS of mud. You are not the first person to come off a beach with this problem - maybe there's something in the salty air that does it. Sometimes the sensors go faulty too, Nissan would have to diagnose that.

I had heard that sometimes the car wants to be completely sure that it can disengage whatever mode it's in before it announces this on the dash, even if it has changed mode and just hasn't sensed it. Again that could be a faulty sensor or switch in the transfer case.

You can safely engage 4WD on grass and try it out, see how long it takes to react.

Could it have been the heat of the drivetrain working hard in the sand causing it to get sticky? Might still be worth a complaint to your dealer and see what they say.

Looks to me like I'll have to hit Stockton Beach one day soon so I can try this out myself.

 

[joe2006]

I have found any vehicle I have driven that engages 4WD electronically can be a bit temperamental at times.

Even with a stick I have had trouble but at least you can push & pull until it finally goes in or out of 4WD.

 

[acko13]

Being an electronically-controlled transfer case, my guess is the sensors hadn't determined that it was "safe" to release 4WD mode immediately.

I can't say I've ever had the problem but I've never been on beach sand - I've done some river crossings, driven through sand on forest fire trails and played in LOTS of mud. You are not the first person to come off a beach with this problem - maybe there's something in the salty air that does it. Sometimes the sensors go faulty too, Nissan would have to diagnose that.

I had heard that sometimes the car wants to be completely sure that it can disengage whatever mode it's in before it announces this on the dash, even if it has changed mode and just hasn't sensed it. Again that could be a faulty sensor or switch in the transfer case.

You can safely engage 4WD on grass and try it out, see how long it takes to react.

Could it have been the heat of the drivetrain working hard in the sand causing it to get sticky? Might still be worth a complaint to your dealer and see what they say.

Looks to me like I'll have to hit Stockton Beach one day soon so I can try this out myself.

Thanks Tony. I could also mention that with the vehicle in high 4WD any change of direction on a bitumen surface seemed to cause transmission wind up. I drove off the sand into the car park and as I turned left you could hear the tyres complaining. My 1992 Pajero used to do this....however the Jackaroo and the Rodeo were OK. On this latest escapade, I had a mate with me in a Toyota 80 series. He too had a bit of trouble getting it out of 4WD in the car park. Strange.

 

[Old.Tony]

Thanks Tony. I could also mention that with the vehicle in high 4WD any change of direction on a bitumen surface seemed to cause transmission wind up. I drove off the sand into the car park and as I turned left you could hear the tyres complaining. My 1992 Pajero used to do this....however the Jackaroo and the Rodeo were OK. On this latest escapade, I had a mate with me in a Toyota 80 series. He too had a bit of trouble getting it out of 4WD in the car park. Strange.

There's a good reason for this.

In 4WD mode the front and rear axles are linked directly - there's no limited slip mechanism between them (like there is between your two rear wheels). When you turn a corner, one wheel wants to go around a larger circle than the other and to do that, it has to turn over more times. Because it's directly linked it can't - and the transmission binds up.

This will cause stretching of your transfer chain (forget the wear on tyres, the cost of this is insignificant). It's best to avoid doing this on any surface where 2WD gives you satisfactory traction.

Just as a note, this is what makes the stock Navara better than many AWD vehicles. Because they have a limited slip function between their front and rear axles they don't get to put as much motive force to the ground when on a slippery surface. They have to buy lockers for the front and rear diffs as well as the transfer case.