My 96 Bronco jerks or thumps from a dead stop, just like a bad u joint but they seem to be fine. I have been told the shaft telescopes due to suspension changes & lubing the shaft will correct this. I can't find a grease fitting. Whats the real deal?

 

My '94 does the same thing. Spicer u-joints are tight, no problem there. I have been told that it is the slip-joint (inside the rubber boot) on the shaft between the t-case and the diff. It is secured by a factory clamp and I am concerned how to re-secure the boot if I cut the strap off. The fix I am told is to shoot some grease on the slip-joint and that should eliminate the problem, at least until the next time. Would really like to hear more on this subject and how it is fixed.

Tampa Bay
'94 EB,5.8,towing package, Rancho RSX7000 shocks,Westin nerf bar, Energy Suspension poly, keeping it basically stock

 

Cut off the cheesy factory clamps, they're just small hose clamps that could be fitted cheaper and faster at the factory - like rivets vs bolts. Pull it apart entirely, slam some grease in there (something rated for high pressure is recommended), put it back together and use hose clamps to close up the boot. Be sure to reinstall in the same spot, ie don't "clock" it from the original position. You _might_ get vibes as the hose clamp can IN THEORY act as a balancing weight but I've never experienced this. Just run the hose clamps screws 180 degrees apart to offset this or even use cable ties if it concerns you. While you've got it disconnected at the rear yoke/companion flange check to see if you can feel any play in the splines by twisting it by hand. If so, it's probably time for a new d/s.

 

Don't want to cut off the boots, then jack up the front or rear (whichever end you are working on), and then using a syringe filled with grease and a large needle, insert it into the boot, and squeeze. You can get the syringe and needles at most feed stores for a couple dollars. Don't get a huge syringe, or you will kill your hand trying to squeeze the grease out! It took me 10 minues to lube up both slip shafts.

 

DON'T CUT OFF THE FACTORY CLAMPS!! THERE'S NO NEED TO. All you have to do is push up on the boot from the bottom and the boot will slide right off. The metal clamps put some tension on the boot and fit in a groove but it's designed to be able to slide off. I've done it three times on my Bronco. I usually just leave the upper strap in place. One thing to note: if you want to fix the problem make sure you remove the female from the male end, clean off the old grease and then use Ford's Premium Long-Life Grease NLGI#2, Ford part# XG-1-C. It comes in a grease gun tube. It's only a few bucks at the dealership. That is the grease that the Ford books specify for the drive shaft. I did this once and did not remove the lower half of the driveshaft from the upper and it did not help a bit. I use an old toothbrush to clean out the female splines and then put grease back in using a thin long handled brush or my finger in a pinch.