This is a 1310 DC shaft. The rear part of this has a zerk fitting. What type of fitting is shown and how do I grease it?

 

I believe that the fitting on the u-joint is just a plug. Remove it and put a zerk fitting in and grease it, then put the plug back in.

 

It looks to be the right size for that. Is there a reason not to just use a Zerk?

 

Some u-joints don't have the room for a zerk when they flex. Those usually have a flush high pressure fitting.

 

That's a needle-type grease fitting. You need to get a needle adapter for your grease gun to grease it. All auto parts stores carry them.

 

That makes sense. Thanks.

 

There is room for a zerk fitting there. However, a lot of high performance drive shaft/u-joint assemblies are balanced with just the plug installed. Installing a zerk can believe it or not sometimes cause a high speed vibration. Chances are you'll never notice it in a Jeep.

 

exactly. you will need a needle and you just stick it in the center of the fitting.

 

A needle isn't quite what you want to lube a flush fitting. A needle fitting is more for injecting grease under a rubber seal.
A needle will contact only the check ball in the fitting, and not seal around the fitting. Plus, it can damage the ball and spring.
You need an adapter on the gun which seats in the socket around the check ball in the fitting. Then the only thing that opens the ball is the grease pressure. The proper adapter will be tapered and rounded on the end. The end will be about the size of the socket on the flush fitting.

 

You wouldnt happen to have a picture?