How do you 2005. Jeep Grand Cherokee. differential service?

Answer 1

Secure the vehicle so it can't roll.
Unbolt the differential cover catching old oil in a big drain pan.
Clean the housing and the cover with a clean paintbrush and Brake cleaner.
Scrape all residue from the mating surfaces of the housing and the cover.
Replace the cover using a new gasket. Install all bolts hand tight then tighten them down evenly but do not overtighten them. Fill up to the level of the inspection/fill hole with the correct gear lube recommended in your manual.
Don't forget to replace the inspection plug.
I prefer Valvoline 75w140 full synthetic gear oil because it is rated for all Dana/Spicer differentials whether they are open or limited slip.