02 Pathy LE - transfer case buzzing?

[NY02PathyLE]

Hi all, new Pathfinder owner here! I have an 02 LE with All Mode, silver with black leather, 82k mi. Second owner.

I noticed that there is a buzzing sound coming from the transfer case while the car is in drive while the transfer case control dial is set to AUTO, 4HI and 4LO. The noise does NOT occur at any point when the truck is in 2WD. If the truck is in park the noise goes away. As far as I can tell the truck drives fine while in 4x4 and everything works, but the noise is there. The fluid level is fine and there are no leaks. There is no vibration while driving.

Anyone care to hazard a guess? Thanks in advance!
Modified by NY02PathyLE at 7:18 AM 12/7/2008

[93'Jag90'325ix98'QX4]

Im from Buffalo too! I have a 98 QX4 and I just got it back from the shop today. It was making clunking noises on occassion even after I had replaced rear linkage about a month ago. This time the front sway bar linkage was replaced along with crappy calipers and seized up pistons.

However, they noticed when driving a similar "buzzing as you describe". Its a hard noise to describe, almost like a twirling fan too ONLY when you're driving like you had mentioned, not in Park. But mine does it in 2WD as well. The mechanic shop replaced my transfer case fluid and they believe it may have a very slow leak considering theres nothing ever on my garage floor. The Q never made this noise at all when my mother first bought it @ 103K miles about 4 months ago. Now it has 105K and she just recently told me this the other day. I havent driven the truck in weeks.

The clunking is completely gone and breaks feel great now. But there DEFINITELY is a similar buzzing/twirling noise as you described with your 2002 as well.

Lastly, the shop noticed and almost assured me that the transfer case in my Q was already replaced with a used one because it had the yellow writing on it from some junkyard they believe. Any thoughts, comments, etc would be greatly appreciated. I have the Q in 2WD right now and it will stay that way so theres less wear and tear.

[razzlerdazzle08]

Actually if im right their is another forum on here that mentions this problem. I am not sure I am correct but their is an electric pump on the transfer case that pumps oil at low speeds. If this is true and this is bad then I would imagine a pump would make the noise you are describing.

[93'Jag90'325ix98'QX4]

yup. I did a little further searching on the forums with the key words instead. I found that the transfer case is mainly lubed by a mechanical oil pump, which is run off the front wheels/axle spinning...aka...I can hear this noise when driving, not while just sitting.

There is also a small secondary electric pump tat operates when the car is standing still.

This was very helpful info I found but now the question is....why can I hear this buzzing/twirling noise when I'm in 2WD too???