Strange rear axle noise.help please!
 

My 99 classic 4x4 is making strange sounds. When at slow speeds I hear a slight grinding noise from the rear, as I speed up it becomes more of a whine but at around 60 it goes away almost completely. At first I thought it was coming from the driver side wheel area but I figure it must be coming from the differential?? Is the rear end going out or could it be something else? Also if I do have to replace the rear end how hard is it to do and how much $$ am I going to spend? Any advice is greatly appreciated! Thank you.

take it in before you get all wound up about pulling your rear end
when was your last brake service? are your shoes shot?
get a pro opinion....
call around and find a shop that wont charge you for a test drive

Good advice, a free check up would help,Thanks. I'm just worried because its my daily driver and it can't be out long. If I know I have to drop and replace the rear I'm hoping to do it myself on a weekend but have never done it.

The vehicle is fairly new to me so I don't know about the last brake service.

sounds like brakes or low gear oil. is the rear end gear cover dry or oily?

Dry

Didn't have time to take it to the shop but today but I called a reputable mechanic, he said it could be a wheel bearing or lack of fluid. As you can all tell I'm mechanically challenged but I really want to tackle everything on my new Jeep my self. My experience is limited to oil changes and a couple front disk brake jobs. I don't know how to check the rear fluid or dig into my rear drum assembly. I dont see a fill hole or drain plug on my differential. Any thought on the noise I hear, why it goes from grind to wine to gone or advice on where to start looking for the problem would help. I will have alot of time to dig into it tomorrow so let me know where you would start.