To change a front differential, do you have to take it all apart.... it's for a GM serria 2000

https://www.gm-trucks.com/forums/topic/119365-pinion-seals/

I believe there is a special blue fluid for the differentials I want to say versatrac? But don't quote me. Your vehicle owners manual is the best resource for fluids capacities and bulb types. Fyi

that sounds right

2000 GMC TRUCKS SSERIES JIMMY 4.3L 6-cyl Engine Code [W]
Differential, Front......GL-5 All TEMPS......80W-90 Manufacturer recommends GM part no. 1052271 or equivalent Do not add limited slip additive.
Differential, With 7.25 RingGear Front..........1.2 liters
Differential, With 8.25 RingGear Front..........2 liters
Differential, With 9.25 RingGear Front..........2.8 liters

There is a drain plug and a upper fill plug on the front differential, and believe it's in the passenger side. but i could be wrong on the side. The age thing but you can see both of the plug than you need to drain and re-fill.

2002 CHEVROLET TRUCKS SILVERADO 1500 PICKUP 5.3L 8-cyl Engine Code [T]

Differential, Front / Rear Full time 4WD......GLS ALL TEMPS....Synthetic Extreme Pressure (EP) Lubricant 75W-90 (SVG)

GM part no. 12378557 or equivalent Do not add friction modifier.

CAPACITIES:
Differential, Front..........1.7 liters
Rear differentials
Differential, With 10.5 RingGear Amer Rear..........2.6 liters
Differential, With 11 RingGear Dana Rear..........4 liters
Differential, With 11.5 RingGear Rear..........3.6 liters
Differential, With 8.6 RingGear Amer Rear..........2.3 liters
Differential, With 9.5 RingGear Amer Rear..........2.6 liters
Differential, With 9.75 RingGear Rear..........2.8 liters

Good luck and this should help.

There should be a filler plug on top of the diff housing, it will have a square recess that will accept a 3/8" drive extension for removal.

It should be listed in the owners manual, but because of different oil cooler setups you may have to do the change yourself and add oil until the correct level is established..... for the first oil change.
Most likely 7 liters,but start with 5,run the engine to fill the oil filter,let it sit for 5 mins and recheck and fill to full.
Note the amount needed for next time.

give these peoples a call they only sells GM-parts only its Schram auto & truck parts 1-800-292-1032 and they website is www.schramauto.com and i hope i have been some help to you Michigan Man.

are you sure it isn't the cv joints making the noise. They are usually noisier when turning corners.

To get it new from GM you probably have to buy a COMPLETE front electrical harness. If its become totally not repairable, try a salvage yard. Show them what you want, hopefully they have a late GM wreck with just what you need. They cut the harness. You have to splice, solder, and reconnect. Be sure to insulate wiring as needed. Hope this helps