XJ99

Anybody out there know the size of grease fittings I need to install onto the front and rear drive shaft before I pop off the sealed caps?

4.3L XJ

1/4 X24 threads. They are standard

XJ99

Hey Cool! Thanks for the info. Just to check though, that's for a '99 Cherokee too? And are the caps steel or rubber? I haven't really looked at them well.

Cheers.

5-90

Are you quite sure about that? 1/4"-24 is the thread for the strap retaining screws (1/4"-24UNFx1" screws,) but most zerks I've seen use a 1/16" NPT thread to go into the part. The principal variation comes in straight nipple, 45* nipple, or 90* nipple (or socket nipple - which is uncommon.)

4.3L XJ

Your right., my bad it is 1/4X28

5-90

You caught me off - it's 1/4"-28, not 1/4"-28. But still, I thought zerks were mainly threaded 1/16" NPT (I've seen some that were threaded 1/8" NPT, but these were on industrial equipment, and some where for filling hydraulic fluid instead. The nipples were the size of the end of my pinky as well...)

4.3L XJ

I have tapped xerk fittings and used the coarse thread tap out of my set for 1/4. Fits exactly.

5-90

1/4"-20 UNC? Interesting...

XJ99

I've been reading all the replies. Thanks for all the info. 1/4-28 seems to make sense after talking to the local parts guy. He was caught off guard when I asked for 1/4-24 grease fittings. He mentioned he only had 1/4-28 threat zerks. So, I guess through process of elimination I'll go for the 1/4-28 fittings. I'll see what happens. It's always good to have a second opinion.
Also, on another note, if my Universal Joints don't have fittings, I guess there's no other way to lube 'em up eh? Besides replacing them with greaseable one's or until they fail.

Thanks for all the help, eh!

5-90

For the second - correct. Before you put them in; squirt some good grease into the open cap, replace the cap, and then roll it around some to coat the rollers. A lithium-based grease should be used if you're in wet environments (like a trailer bearing grease,) a moly-based grease if not (it's slipperier, but not water-resistant.)

Next time you get Cardans, specify that you want greasables. Then, open the box and make sure you get them before you pay for them! A good counterman will have no trouble with it, a great counterman will hand you the box already opened. If neither of those happens, look for your parts elsewhere.

XJ99

Thanks a bunch. I'm trying to save some money so I'll try to knock out the UJ's on the cheap and pop new ones in, hopefully with some level of success. I've seen U-joint's done without any fancy equipment, I just hope it isn't harder than it looks. Fingers crossed.