Cherokee Sport Rear End / Differential noise

[msnow2]

I have a 98 Cherokee sport and I am having a loud roaring noise in the rear end . It seems to go away at highway speed but lower speeds it is very obvious. I have heard some other Cherokee owners talk about something in this area, anyone have any ideas?

[naturalbornmudder]

go buy a copuple of quarts of 90W gear oil and a tube of Permatex High temp. Then pull the cover off of the rear diff and do a visual on it. Remember that gear oil will come out when you take the cover off so be prepared. I would check for abnormal wear in the ring or pinion gear. Lack of diff oil could be the problem itself. I have seen that before.