I've got a 97 dodge ram 1500 5.2 magnum and it just started this weird whiny scraping noise somewhere from the back of the truck, I'm thinking it may have something to do with the driveshaft. It's always clunked real hard in reverse and when switching to 2nd. It's kind of random, but usually either when I press the gas real easy or let off is when it starts. Any ideas?

 

I'd start with jacking it up on stands/blocks put it in neutral and give the driveline a shake down for bad u joints, check the diff fluid level

 

One or two piece drive shaft?

 

Noise on acelerating/decelerating and some what gone when not under a load?

 

I checked my rear differential oil today and it maybe had half a quart in it, so I filled it back up and took it for a drive and it made the grinding alot more quiet but it's still making a grinding and sort of humming noise on on acceleration and decelaration at about 40 mph

 

Being low on oil likely did a number on the bearings.... and possibly the gears themselves..... I would consider just replacing the entire rear end with one from a junkyard.... LOT cheaper than rebuilding...

 

How hard is it to replace

 

To me, the hardest part is removing the U-bolts. Since they should be replaced with new ones, you can cut them with a wizz wheel or a torch (for example, this tool makes short work of them - https://www.harborfreight.com/pneuma...ool-58690.html) If you have patience and some PB Blaster, spray the U-bolt threads with PB Blaster and remove the U-bolts with a deep socket and ratchet. Check car-part.com for salvage yards in your area that have a rear axle available. If your truck is 4x4, make sure the gear ratio matches the front differential.