If you want to go the cheap route, and save up for a ARB for awhile, this is for you.  Hopefully this will help new people.

Tools

Basic sockets and wrenches, nothing fancy.
jacks stands
220v Welder or similar

Materials

3 Qts. 80w90 gear oil (or a oil of your choice)
1 Qt. of Dot 3 Brake fluid
Brake Cleaner
RTV gasket maker
1/4" plate steel, 2" x 6" is plenty


1.Jack up and secure your rear axle on jackstands.
2.Remove both rear wheels, and drain the diff oil.
3.Disconnect the brakeline fitting at each drum, and plug the line so it doesn't drain out over some hours.
4.Remove the 4 nuts/washers on the inner part of the drum that secure the axle shaft/brake drum to the axle housing.   Repeat on the opposite side.
5.Slide each axle shaft and brake drum unit out, making sure not to rest the axle shaft on the oil seal in the axle tube to prevent leaks in the future.  Set the axle shafts aside.
6. Disconnect the rear drive shaft from the pinion flange.
7. Remove all 3rd member nuts/washers, be prepared to catch the 3rd member when you remove the last nut.  It weighs about 50lbs.
8. Now take the time to thoroughly clean the spiders gears, center pin, and ring gear so oil isn't dripping over your cleaned spider gears.

cleaning


9.Cut and test fit the plate steel so it sits in the spiders

10.Plug the axle shaft splines with moist washcloths or something to prevent slag build up on the teeth.
11. Make large tack welds on the center pin to the small spider gears.
12. Now install the Plate steel and weld it solid.  Do one side, wait 10 minutes, and repeat until all 4 sides are welded.  Then flip the carrier over and install the second plate steel and repeat the process on that one.

13. Once its welded solid, and you didnt overheat by nonstop welding, clean it up and any slag that might have formed on anything.
14. Clean the gasket surface and RTV it

15. Now re-install in reverse to steps 1-8
16. after re-attaching the brake lines, bleed your brakes with a tube and jar, or brake bleeder.

Now you can go places you wish you could before. And barely spent a few dollars. Enjoy 

So if this was done as a temp locker until you got a locker, this would be removed and replaced by the locker? All gears or just ring gear? I am 100% new to lockers... 

Dan

I think I'm gonna redefine newbie here but can someone toss down a quick explanation of what this will help with? I've got a dead stock 81 yota 4x4 22r that my buddy is bit by bit explaining to me and I'm scouring threads here trying to figure out what I can but I could use a beginner's bump.

Your toyota has open differentials. So instead of having an axle that will send all the traction to the non gripping tire this will send equal power to both. It's not the greatest on tires and being quite (chirps when making tight turns) But it will greatly improver your offroad ability!

Is this not a good idea for a dd? I just figured over time, and wouldnt take long, that the shaft splines would have been torque a lot and loose strength. But thats the risk huh, it be smarter to run cromly shafts...and arb's.

What im asking is how long would welding the rear diff last?

Welding a differential is a very permanent thing it turns out, and it will have side effects when it comes to all of the times you’re not doing a maaaad skid through a corner. You should also definitely make sure you know what you’re doing first, because you will very easily ruin your car.