I think my front drive is going out. Could use some advice please.

One lesson I learned with the same issue, don't blindly start pulling it apart. As safely as you can, recreate the problem while the truck is jacked up, and know for sure first.

Long story short, mine only did the same thing at a specific speed, which of coarse was in the same gear (30mph gear 6) the noise and thump travelled through the drive line so very well the shop immediately pulled the trans. Nope, not the problem... must be the front diff, Nope. I just love shade tree mechanics that pose as legitimate good shops!

The power divider only acts as its own differential splitting power to front or rear as needed. Meaning the front drive is not your default drive with power divider unlocked, it can be either front or rear.

Good luck!

 

Stick a magnet in the oil fill plug hole all the way to the bottom, on both diff's, and see what comes out.

 

Just do a quick plug swap on both diffs.

I think you'll find your answer real quick .

 

I vote for jack stands. In my case they jacked it up and put it in gear. The noise was obviously in the rear of the truck. Then they took off the intermediate drive shaft between the diffs and spun it up again. The noise was still there, so we knew it was the front diff. They opened it up and a bunch of rollers fell out from the bearings,

 

You may not get much scrap from a trans because they have magnets in the bottom of them. Just check before you you pull stuff apart is the point. You started with the old girl may break you and, unless you put the old oil back in, every box you drop the oil out of is about $100. I just hoped to prevent what happened to me as a lad.
Drove the truck and told the boss it does X Y Z. That's the front differential pull it out. I pulled it out but I don't see anything wrong. Oh! Then it's the rear differential, pull it out. I got it out but I don't see anything wrong. Oh! Then it's the transmission pull it out. I did not say anything but thought power divider or transmission. Knocked the top off the trans, bingo.
It is probably the front rear but check it anyway you want and spend your money on the problem.

 

You don't have to drop the oil out of anything .just do a quick plug swap to see what's on the magnet.
If something is coming apart in the diff you'll see the carnage right away on the plug

 

Pull the fill plugs and see if one has really dirty looking oil, if one does its likely the culprit. Then pull the drain plug and see what you get.