Your reasoning about the assembly line labor savings is as good
as any I've heard Grigg, and it might have entered into the
equation. It does however give you twice the bearing surface of
a fixed bushing, which could reduce the friction giving you
easier steering, could even result in less wear than a single
surface bearing all of the stress.
You know me Grigg, the eternal doubting Dennis. I sort of doubt
that any of anaerobic compounds, resulting in a cast filler,
could stand the loads imposed on the king pins, especially upon
impact with poor roads surfaces. Just taxing down a smooth
asphalt runway before take off at only a few miles per hour
with my 750lb. Pitts special would peg the recording G-meter at
over nine G's. I'd shudder to think what sort of impact loads
the front end of a 3500 lb. vehicle would encounter at fifty or
sixty mph but I'd bet it would be well into the double 'G' figures.
The plastics used in your newer truck is most likely an
injection molded material which gets much of it's strength from
the long molecular chains as opposed to a cast part. Probably
something like a "T-series" resin which can handle pressures up
to 32,000 pounds per square inch and temperatures up to 619F.
The Loctite 620 has a shear strength of about 3500 psi. Not
familiar with the "660" but there is a Loctite 680 high
strength that has a shear strength of 4000psi, but it's only
designed to fill a loose slip fit no more than .015".
Have to take a look at Rock Auto's site Caso, I'd like to add
those dimensions to my reference file, thanks for pointing that out.
Denny Graham
Sandwich, IL
