2000 tacoma, 4wd, 3.4l v6

So I went to grease my drivetrain, and got to the zerk fitting on the rear driveshaft (the shaft itself, not the ujoint).. I started pumping grease, and it came out the back of the driveshaft! So I've looked at a couple of other tacomas and they all have seals on the back of the driveshaft.. apparently, mine is missing in action. I attached a picture so you can see the seal I'm talking about.

does anyone know what this seal is made of? or how I can seal it back up? I went to the local stealer and they never heard of this before and couldn't offer a part. the tech there basically said plug it with a rubber stopper

 

Usually just a rubber or metal plug there. You could just shoot a little RTV in there. If you put in a solid plug, leave a small vent hole in it. This is to prevent pressure buildup if you bottom out the shaft fast (it is like a sealed piston otherwise).

And one tip on greasing the slip yoke, don't put too much grease in it. While you could easily pump a whole tube in there, you'll just fill the cavity and then the slip yoke can "hydraulic" on the excess grease if you bottom out. I only put in about what the other fittings take. So if the u-joint fittings take 2 pumps on the grease gun, I'll do 2, maybe 3, pumps on the slip yoke.

In fact, the main reason that plug comes out is if the slip yoke was overfilled. Just like the way the grease gun easily builds up 1000's of PSI from the pump handle, you can do the same with the grease in the slip yoke.

 

thanks for the info.. but what is RTV?

 

Room Temperature Vulcanizing (A.K.A. silicone) sealant.

 

gotcha. thanks