Squirting some grease this evening and the fittings on the rear leafs are blocked, no amount of pressure would force grease inside. All the others were fine. What is the procedure? Pull the zerks and clean stuff out?

 

If we are talking about the same truck as the one in your avatar.NICE TRUCK!
And yes,I would remove the old ones,try and get all the old grease I could out,then install new fittings,sometimes a little heat on the opposite side to kind of draw the grease towards it works also.

 

Have you tried an air grease gun?

 

I had the same prob. and took a propane torch to the front and back side. A couple of seconds later I had grease spooging out. Make sure you don't touch it!

Good luck and be safe. Stay away from gas and brake lines.

 

Have no access to an air unit, but I will try a torch, thats worth a try before dissasembly!

Thanks to all!