alright just tried the 4x4 feature last night ( first time on my 2008 Pathfinder).
I feel like I need to press a little bit more on the gas pedal to move the SUV: I understand you need to move the 4 wheels when going from 4x2 to 4x4. Just wondering if it is normal, I guess using the front differential use quite some power.
When I switch back to 2WD I get the power I'm used too on the freeway.
thanks !
question for 4x4 owners
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> on grass/over the curb
Hahahaha...
It's just binding in the drive line, that's normal. When you turn in 4x4 mode you're forcing the tires to all turn at the same rate when they don't want to, so some extra power is needed to get the tires to slide a bit.
Imagine the 4 tire tracks on the ground as you continually turn, it's 4 entirely different paths. As you complete 360 degrees and look at the circumference of the 4 circles clearly some tires have rotated more than others right? And the tighter the turn, the more extreme the difference. A 4x4 system is going to fight you, trying to make it so all tires turn exactly the same amount, hence the need for some more power to make it do what you want. Being on a slippery surface, or having a limited slip center diff, will reduce this tendency, but it'll still be there to some extent.
Hahahaha...
It's just binding in the drive line, that's normal. When you turn in 4x4 mode you're forcing the tires to all turn at the same rate when they don't want to, so some extra power is needed to get the tires to slide a bit.
Imagine the 4 tire tracks on the ground as you continually turn, it's 4 entirely different paths. As you complete 360 degrees and look at the circumference of the 4 circles clearly some tires have rotated more than others right? And the tighter the turn, the more extreme the difference. A 4x4 system is going to fight you, trying to make it so all tires turn exactly the same amount, hence the need for some more power to make it do what you want. Being on a slippery surface, or having a limited slip center diff, will reduce this tendency, but it'll still be there to some extent.
First things first. You need to get out in the dirt. Even a small patch of dirt road will work, but that's when you can pop it into 4x4 and have at it. You can still feel the binding a bit in the dirt, and almost a shimmy effect when cranking tight turns. But, the dirt compensates for all of that because there is give under the tires, as opposed to no give when on a solid surface.V8Pathy wrote:also it seems if you are turning (like a U turn on a one way street) it is slower or require more power..
About your U turn, was it a real slow one, or was it at a pretty good clip? I haven't noticed any loss of power when doing U-turns, but I do notice that the VDC kicks in when I do things abruptly, which makes it feel like I'm riding on the back of a turtle.
Whatever the case might be, it would probably be a good idea to start documenting all the times you notice the drop in power. It will come in handy if something is wrong with the vehicle & you have to explain what's been happening.
I've had a lot of 4x4's and it seems like the less torque the more you notice power loss when locked into 4wd. Some examples are:
I had a '98 Ford Ranger w/ the 3.0L V6. On top of low power, it was a 5speed manual so it was even more noticable how much it was robbed of power. In 4wd on the road (like in snow) you had to REALLY hit the gas to get moving, you could really feel it.
I also rented a Jeep Wranger 4cyl in Aruba a few months ago to drive the back side of the island. It was also a 5speed manual. When starting from a stop I could tell that it was down on power in 4HI big time.
On the other hand, I can't really feel any power diff. in my Bronco w/ 400 V8 at all.
You are turning a whole lot more moving parts, and if everything isn't exactly even (same tire wear front/back, same EXACT gearing front and back) you are going to doing a little binding too.
I had a '98 Ford Ranger w/ the 3.0L V6. On top of low power, it was a 5speed manual so it was even more noticable how much it was robbed of power. In 4wd on the road (like in snow) you had to REALLY hit the gas to get moving, you could really feel it.
I also rented a Jeep Wranger 4cyl in Aruba a few months ago to drive the back side of the island. It was also a 5speed manual. When starting from a stop I could tell that it was down on power in 4HI big time.
On the other hand, I can't really feel any power diff. in my Bronco w/ 400 V8 at all.
You are turning a whole lot more moving parts, and if everything isn't exactly even (same tire wear front/back, same EXACT gearing front and back) you are going to doing a little binding too.
I believe it is referred as " Heavy Tight corner braking symptom" on the Nissan Tech website.
See here:
http://www.nissan-techinfo.com/nissan/r ... er/DLN.pdf
page 120
See here:
http://www.nissan-techinfo.com/nissan/r ... er/DLN.pdf
page 120
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