Why does it look like there are two sets of steering arms? Upper to the front and lower pointin to the rear with TWO tie rods?
I don't "dislike" plastic, and agree that in the right application it can be perfectly suitable. In this case we don't know what it is, delrin, acetate, urethane, or what? We do know that it is under constant compression from the u-bolts where almost any plastic is more likely to deform or fail than metal. Failure of that particular part could be catastrophic, So why not play it safe.
At the Safety Center I worked at as a lad... Big Chevrolet/GMC 9-yd. dump trucks would come in for wheel alignment, I'd raise them and shake them down. Much as 1.5 degrees variance at king pin. Tear the kingpins out and here was the magic bushing design! Plastic. Hammered to shim thickness. We kept a large stock of metal kingpin bushings to cover this/these.
Correction, the plate under the spring is steel and is powder coated steel. It was put in there because the axle needed to slide foreword to center it in the wheel well. There is a pin in the plate to locate in the spring center bolt hole, then there is another hole to the rear of the plate for the spring center bolt. I thought of machining the plate at a 5 degree angle but I that would make the plate too thin at the rear to engage the center bolt.
Caster shims installed which dropped the axle .440 at the plate but it also dropped the drag link and it rubs on the spring! I ground off the ends if that spring clamp for clearance but the link still rubs lightly and will rub harder under a load. PS I have a perfect 5 degree caster now!
It's easy to swap the center bolt and use a bushing or washers to space it so the shim wont make it too short. I buy 3/8" Allen cap screws and space them up so they fully engage the perch through a spacer.
The Jalopy Journal
