4x4 noise

[Colombia81er]

So I got a 98 path and with all this snow I been using my 4x4. But the other days I noticed that when it was engaged and I would make a turn I would hear a grinding noise as it was my axles. So I went back to normal driving and the noise went away.

My question is what would cause the noise only when its in 4x4 and no matter what direction I turn it will make that noise.

[atraudes]

It could be a few things causing this noise. How loud was the grinding, and what type? Was it loud like metal tearing into metal, or more like that sound the transmission makes when downshifting?

My best guess right offhand is that it had to do with your differential being locked in 4WD, so I'll elaborate a bit so you can decide if this was the case for you.

The answer sort of depends on the 4WD system that you have. My 2001 QX4 has 4 modes: 2WD, Auto, 4Hi, and 4Lo. In 2WD, obviously, only the rear wheels are engaged. When in Auto, the system automatically decides when to engage all wheels. When in either of the last 2 modes, all 4 wheels are engaged and the differential is locked. The difference between the last two modes is gear ratios, meaning you get more torque with the Lo mode, but couldn't get above 50 or so.

All that being said, what's relevant to you is the bit about the differential being locked in 4Hi and 4Lo modes. This means that all 4 wheels are rotate at the same speed all the time. When you make a turn, however, the inside wheels of the car are going to want to turn at a lower speed since they're not traveling the same distance as the outside wheels. If the differential is locked, the strain of the inside and outside wheels not wanting to turn at the same speed is sent to the transfer case, putting a whole bunch of stress on the components inside. So, it's recommended that these modes aren't used unless you're dealing with slippery or non-asphalt conditions, like snow, ice, or loose dirt which would allow the wheels to slip properly.

So, unless you have the knob-style 4WD selector and you were in Auto, I have a feeling the noise you were hearing was the transfer case crying out in pain.

[atraudes]

I should mention that the differential I'm referring to is the center differential. There's a decent read about it here: http://4wheeldrive.about.com/cs/ttdrive ... 61503a.htm

[Colombia81er]

Thanks for the Info. Its an automatic I don't have the blades but the noise sounds like if the axle was broken. The weird thing is that only makes that noise when is on 4x4 hi or lo

[atraudes]

Then yeah, you're probably right, it's likely something broken.

If the axles look fine, take a look at the (can't remember the names) bit that slips in and out of the hub in the wheel when engaging/disengaging 4WD. It's possible the teeth have been ground down so that it's slipping like a screwdriver in a stripped screw. That would also explain why you only hear it while turning; when driving in a straight line the wheel and drivetrain are moving at the same speed, and when you turn, the wheels turning at different speeds from the drivetrain could make the problem audible.

I feel like I'm rambling so I'll stop

Best of luck and let us know how it goes!

[Colombia81er]

Another question. So we was hit with about 14in of snow these past few days. When I put it in 4lo-hi it will just turn one wheel in the back and a other in the front FL-BR or vise versa never all four.

What could it be.

[Arrow]

To quickly answer your latest question your problem is probably that the differetial fluid needs to be replaced (for the rear diff) IF you have a LSD in the rear (should have a sticker on it saying LSD). However the front will only apply power to 1 wheel because the pathfinder did not come equipped with a LSD front differential or an electronic locker for the front. So basically you will always have power shift to the wheel that is slipping the most on the front.

[Leo1998]

check this out...covers 1996-2004 may help http://www.faqs.org/car/nissan-pathfind ... uspension/