Lower front a-arm removal
 

Installed the front lower a-arm jimlab bushings and had difficulty removing the lower a-arm. Jimlab's techniques did not work in my application so I resorted to applying more "confrontive" measures.

There is a tool called a hydrualic jack--has a cylinder like device on the end of a hose that comes out when pumping the handle. It doesn't come out that much maybe 1.5".

first, I supported the rotor on a jackstand while I removed the bolt securing the upper a-arm...12mm? I did not remove the upper a-arm chassis bolts. I then removed the top caliper bolt and disconnected the hardpipe brake line and hung it over the steering knuckle bar. Removed the front sway bar and left the link to the lower a-arm on the a-arm intself. I have found remounting the sway bar much easier then attaching the link with it attached to the sway bar. Anyhoo, disconnected the link from the sway bar, remove the lower shock bolt (on the a-arm). This leaves only the lower knuckle left. Remove pin and loosen castle nut til flush on bolt (I actually removed the nut altogether on the other lower a-arm. If you remove the castle nut then you wont have to worry about the whole bolt turning while trying to remove the castle nut!) I then stuck the cylinder of the jack in between the knuckle bolt and the upper a-arm iron and started jackin'. The jack leveraged the knuckle using the upper a-arm attachment. Very loud when the lower knuckle popped out. Nothing damaged at all...the pop sorta skeerd me though!

Looking at the pressure required to remove the lower knuckle, I would have beaten the nut to death with a hammer. This is the first time the knuckle was removed,,,65k mile car. Second time will not be so difficult I'm sure!

I tried Jim's technique at first, and thought I'd have to knock the car off the jackstands before it'd work that way. Also couldn't get the "two-hammer resonance" technique to work. Ended up using the hated pickle fork since I was replacing the lower arm anyway. Turns out the fork didn't damage the joint, so I'd probably go that route again.

However, I like your jacking idea, although I imagine it puts a lot of stress on the upper joint if I've visualized what you're doing correctly.

No matter, pressure will be required and must be placed somewhere to remove the lower knuckle. I would prefer placing it on the cast iron hub then then hammering the threads. I did this twice successfully without a hitch.