How was the gear diff of vintage pan car adjusted?

[polarbear]

Before the ball diff era (RC300BD, CK800SJ, Serpent MK3), was there any design or tech to adjust the gear diff , (say AMP, PB, SG etc)on 1/8 pan cars??
There was no super thick silicone oil then??

[Lonestar]

You could always use non-silicone mechanical grease, there's some thick stuff out there. But given the tire quality bitd I kind of suspect people were looking for a free diff rather than a stiff one

Some of the conical-gear diffs had a setscrew to adjust the "pressure" of the planetary gears that would actually "bind" the diff. A bit anti-mechanical, but it worked. I know this technique was still used in the early 90's on some 8th scale offroaders too, but it has disappeared since then afaik

Paul