just rtv for a gasket?

[lukecp]

Unless its to cold this weekend, i am going to change the fluid on my dying 12-bolt rear axle for its last 80-mile trip home on Tuesday (pinion bearing is shot).
A member on another board suggested i change it so i might be able to get a few more miles out of it.

Anyway, i don't wanna pay $5 for a new gasket since i am only driving it an hour and a half or so, and i have tubes of blue, red, and black RTV in my truck. I usually coat my gaskets in RTV, but i have never used it alone before.

If i just use RTV, will it work without leaking too much on that short of a trip? Which RTV would be preferable to use? I'm thinking black or red...

Thanks for any help