Yes, I put a new gasket on mine, but then it was leaking badly within a few months. I thought it was just a bad gasket, but I noticed a few indents around some of the bolt hts in the diff cover that were possibly caused by over tightening. I ended up getting a new diff cover ,( Dorman brand ) which was a LOT thickertmetal than the factory diff cover, plus it has a drain plug. It came with a new gasket as well which was MUCH thicker than the thin Fel-Pro paper gasket I installed months earlier. So to be honest, I would just go ahead and get a new diff cover too. They are a lot cheaper if you order it from Rockauto (around $25 I think) which is not bad considering it better quality that the original, plus it comes with a very heavy duty gasket. The ONLY thing I didn't like about it was that it all bare steel. But a few coats of black spray paint before installing it quickly solved that issue.
And here's another tip, I mentioned that some of the bolts might have been over tightened, so I made sure to not over tighten them this time, however I noticed some small dripping/seepage a few weeks later, so I checked the bolts and some of them were VERY loose, as if they worked their way loose. So I tightened them up, cleaned off all seepage and kept an eye on it. I climbed under the truck about 2 weeks later just to check if the bolts we're tight, even though nothing was leaking, and sure enough two of them were a little loose. So after that what l did was torqued them all down, and then I used a silver paint marker (white would be better though) and I drew a line on the head of each bolt and onto the diff cover. That way I can check to see if the bolt have loosed by simply sticking my head under the back bumper and not grabbing a ratchet and actually check each bolt. You can VERY easily see if the line on the bolt head has moved from the rest of the line on the diff cover. So simply marking the bolts is a good tip to check for bolts coming loose with a quick visual inspection and not even touch it.
