I have a 2005 Dodge Ram 1500 with the 4.7L in it. Yesterday, on the way to school, i thought a heard a little whistling noise while driving down the road. Now it is a whining sounding noise that sounds like its coming from the rear end of the truck. If your cruising down the road and throw it in neutral, it still makes the noise making me feel like its not the tranny. At some speeds, the noise sounds like the noise the low fuel indicator light makes but constant. Anyone have any idea what it could be? Maybe the rear end gears are exploding or could it possibly be a wheel bearing? Thanks for any advice. I have 85,000 miles on my truck.

I don't know if it's your rear differential or not. Mine was making a really loud groaning noise, but only when turning, going straight wasn't a problem. I changed the gear oil and it turns out I had a c-clip broke also. Luckily after changing the oil the noise stopped. Does the noise stop when you apply the brakes? Does the noise intensify at different speeds? It could be a wheel bearing or the brakes.

If you've got the factory LSD, then I'd be pulling the rear diff cover ASAP and doing a visual inspection for a "C-Clip" or pieces of one getting into the teeth of the gears. VERY COMMON and if you catch it early enough you might can save the differential.

Do a search for "C-Clip" in this section and read in horror...

The noise is on whether breaking or not and it does intensify with different speeds.

Yeah I just have an open rear diff and not an LSD.

Have you checked the fluid level in the rear?

I haven't checked the fluid level yet but last year it got changed bc my rear pinion seal was leaking. How do you check it?

There is a black rubber plug that you pull out on the back of the diff. cover, the level should be up to the bottom of the fill hole or very close to it.

I checked the fluid level which was fine, and also cracked open the rear diff cover. Nothing looked out of the ordinary. There were some metal shavings but isnt that normal? I put royal purple synthetic back in it and it doesnt seem as lout, but it still makes the same noise

Shavings are normal, chunks would indicate a problem. Next step would be to take it to a 4x4 shop that does a lot of work on the dodge 9.25 rear b/c it's a tricky one to get right. They should be able to diagnose it and tell you what they need to do to make it right and quiet again. You can post up here and see if anyone knows any good shops in your area, or if all else fails take it to the dealer. When did you first notice the noise?