The Mitsubishi Pajero Owners Club®

[michaelpotter]

Hopefully the subject has caught yore attention......I'm in the middle of replacing my UJ on the propshaft, no problems there, but in one of the cups there is a threaded hole for a grease nipple,..again no problems, but do I keep the nipple in or replace with a grub screw? just wondering about balance....would a nipple knock the balance out?,....thanks  mike

[Google]

[JPB]

Depending upon how long the nipple is, it may catch between the yolks of each half of the joint as it rotates, I found this out the embarrassing way after believing it to be a good idea to leave the assembly nipples in place after changing all three joints on my Dolomite's propshaft..  If, however, the nipples are stubby ones that don't extend so far from the centre block, they're very unlikely to catch on the lugs of either yolk and can safely be left in place for ease of future maintenance.
The balance of the shaft is more likely to be off as a result of the new component being there as the tube itself - in the case of the longer nipple - is so thin walled by comparison that the material missing from the hole in the block tends to weigh more, bearing in mind that the grub screw is solid.  
The far more significant thing to consider when changing a joint is that the yoke of the new joint should line up with those of the joint at the other end of the section, not at 90 degrees to them. Get that wrong, and not only will the joint be less likely to balance correctly, it will also suffer from a rhythmic pulsing that leads to a rather nasty vibration felt through the car at certain speeds, usually the exact speed that the driver wants to travel at!

(I managed to write that lot without once chuckling away to myself about the name of these components or, for that matter, the use of the word "shaft").

[assassin]

Use the original nipple as these fit between the yolks without catching and the original stubby nipple is easier to get a standard grease gun onto.