Most manuals and YouTube videos say to use RTV silicone for sealing the differential covers, but has anyone tried using/making gaskets instead?
Is there an advantage to using sealant over a gasket or the other way around?

I used sealant when I did my rear diff a few years ago...but I always have a problem lining up the holes, while lying on my back and supporting the cover....a gasket would be so much nicer.

 

Lube locker makes reusable gaskets, I got then for my front and rear differentials and transmission pan and they work great. I believe they were around $30 apiece

 

I use lube lockers also

 

I really like the lube locker. Here's a thread that goes into all kinds of things, but it seems the lube locker is best called for if you don't have a drain plug on the diff cover. If you have a drain plug, then it doesn't really seem to matter one way or the other:

https://www.ford-trucks.com/forums/1...-sterling.html

 

I've used lube lockers but if I install a yukon or similar cover with a drain (like they all should have) i use rtv anymore

 

FYI, Permatex makes an RTV specifically for differential covers. It works very well.

 

Gotta laugh at this....

 

I got lube lockers to install when I change my diff fluids this spring.