Well after living with this project a few more week and getting out the micrometers, 10x loupe, and making up drawings to see how every thing actually fits, I have come to an interesting conclusion. So here is my dumb answer.
What we are calling “rollers” on the AD regulators, actually aren’t rollers at all! The reason I say this is that both the inner and outer are .100” thick leather. You can see the grain on the one side quite clearly at 10x. and they are flexible.
The dimension between the roll formed channel opening (at <.380”>) for the post (at .375”) is made with only a few thousands clearance. For an internal roller to work, what we have been calling “the roller” outside diameter would have to be quite precise to keep the post from scraping on the channel. The leather, “rollers” that are on these regulators are not ridged enough to serve this purpose.
I believe that the “leather rollers” are not rollers at all but actually wicks to carry a lubricant and that the posts that are hollow riveted to the regulator arm are in reality made to drive the channel up and down by sliding in the slot. Although in later years an actual roller may have been used, I believe that the early AD units were just simply a sliding action and not a roller action. This is a very difficult area to lubricate, requiring the removal of the handles and door panel and this is probably why most of them we see are in a worn out condition. Adding to the problem is that the driving member i.e. the post, being round, has a very small contact area and therefore would wear much sooner than a roller. And as has been pointed out many times before, GM did not make these trucks to last a lifetime.
What do ya think???
Denny Graham
Sandwich, IL

Denny G
Sandwich, IL