radius arms

[frankensteined_67]

has any one made new radius arms for there F100 4x4. i have put a 8" lift on my f100 and need new rad arms to make everything line back up and was wondering if any one as any experience on doing this.

[averagef250]

I just cut the stock ones up, set my kingpin angle at 4 degrees and weld them back up. I cut them at both ends, Vee everything very well, blast the pieces, full pen weld with 70 series filler and needle scale (shot peen) the arms afterward. It will move your axle back a bit if you use the stock rear mount location though. The mount's easy enough to move forward though.

I built a pair for a friend who doesn't have the word "gentle" in his vocabulary. I think the radius arms are the only part he hasn't broken.

[tybob81]

broncograveyard.com might have something

[frankensteined_67]

averagef250: your 4^ is what i needed to know and did you add or take off any material off of the rad arms to move them. mine need to be moved about 1.5" forward to put them back to stock position. and i am using the original location and mounts at both ends and i can not move the one on the frame as i have already have to frame finished.

i have tried broncograveyard.com they do have rad arms but they are extended ones.
thanks for your help

[averagef250]

I've seen guys make their own arms by using the front and rear forgings with rectangular tubing in between. They cut thick plate to fit between the webs of the radius arm "I" beam at the axle side, slipped tubing around it and plug welded it together.

Kingpin angle has to be leaned back 2-6 degrees at actual ride height . It's kind of set in stone. Everything from a 1950's Peterbilt to a Formula1 race car uses the same kingpin angle. on a dana 44 I use the flat above the upper balljoint to measure off, it's pretty accurate.

Also, don't use a bubble angle finder. They aren't very accurate, a bubble level machinists protractor works great or a precision angle finder.