I've got a U-joint going out in one of my halfshafts. I've got two new(to me) halfshafts ready to go in but after jacking the car up and trying like the devil to just break torque on one of the nuts, I gave up.

Any suggestions? Seems like these things were not meant to come out simply on their own, you'd have to take apart the rear suspension to get them out. I'd like it to be a simple "4 bolts here, 4 bolts there, now for the other side" job, but it looks like an all day project at this point.

Suggestions, anyone? Can I do this on my own with a couple of open end wrenches, or am I screwed?

I suggest using a closed end wrench to avoid rounding off the nuts. There's not a lot of room in there to recover from this should it occur. I can tell you that many closed end wrenches will be too big around the nut opening to fit in that small space. If I recall correctly, I couldn't get my Craftsman combination wrench's closed end in there and had to use a Snap-On wrench I happened to have. Before trying again, give them several good soakings with a quality penetrant like Aero Kroil or somehting of that nature. If that doesn't work, some well placed heat might help break the nuts free.

What seems to be the trouble? Are you having a problem fitting a wrench to the nuts holding the u joints in place , or are they rusted in place? You will find that you do need to rotate the shaft and attack one nut at a time as the clearance is tight to apply the wrench. Use some PB Blaster or Kroil to the nuts if they are at all rusted. If one u joint is failing the others will not be far behind. I would change them all. Gary

If you happen to have some coarse valve grinding compound, put some on the wrench to give some extra bite and prevent slipping. Soaking in Kroil, heating with a propane torch and repeated soaking first, always seems to work well. I would sacrifice a box end wrench and grind it down to fit, if need be. Good Luck

A.J.

All the tips above are good ideas. I was able to get a box end wrench (craftsman) around the nuts, but I had to rotate the shaft around to find the best location to get the most leverage. It was a while ago, but I remember that I was able to get to two nuts at the 11 o'clock position and it seems the other two were either at 8 o'clock or 4 o'clock (sorry, don't remember exactly on the second set). Anyway, I was under the car for all four nuts. I put the wrench on the ones at 11 o'clock and then climbed under the car and pulled down (in gear, parking brake on) to get them to loosen. The other two I could get to from under the car and rotating the shaft until I got the best position (again seem's like it was 8 o'clock).

I found that there is a particular rotation that allows me to fit a socket on the inner end and then I can use about a 6" extension and an impact gun. But it has to be clocked just the right way for the extension and gun to go on.

All of the above - Kroil is the way to go. If you do any work at all on these old Z's a couple of can's of Aero-Kroil are simply indispensable. I've been working on cars for 50 years now, and I've never found anything that comes close to being as effective as Kroil. It's a pain in the neck to have to order it on-line, wait for it to be delivered - and it is not cheap; but well worth the time and effort. Put Kano Labs in google...

If you can't get an air or electric impact wrench on it - then resort to the original impact source. Everyone should have a medium size brass hammer in their tool box.

So - Kroil and let it soak, then box end wrench on the nuts, then a swift solid blow to the other end of the wrench with the brass hammer... They break right loose. Dynamic torque is soooo much more effective and far easier on your hands....

FWIW,

Carl B.

All excellent advice. Thanks everyone.

Unfortunately I'm fighting off a nasty flu bug right now, so it'll have to wait 'til I'm feeling better. It hit me like a brick wall yesterday.

I did what Geezer mentioned. I grabbed a POS Made in Taiwan Long Box end wrench and ground it down on the grinder so it was a little thinner and fit between the nut and the half shaft body.

Once I was able to get the wrench on there, They finally cracked loose and unscrewed easily. I personally use Liquid Wrench. It's easier to find and inexspensive but does the job. I guess I'm luckier than most, My 70' was 95% rust free when I got her. Only broken bolts were the fender screws where the hood closes. I snapped two of them and the other fender screws under the cowl on the drivers side.

Dave.