Diff lock question

[Serviceguyuk]

Hi chaps,

Before your eyes start rolling back in your heads, my question is a little different.

I recently bought a R2hobbies Merc Actros 6 x 4 as the price is pitched 10% less than Tamiya here in UK and they don't do a 6 x 4 anyways. During my build I came to the diffs and started the usual greasy mess that always ensues with this. During final assembly I noticed two things #1 They stiffed me on the parts and I got three of one drive shaft and one of another where I should have got two and two (I got over this with a little ingenuity) but #2 and finally my question, each 40T pinion gear has a castellated end to it as you can see from the extract below.

Add this mysterious design to the equally mysterious hole in each half of the diff housing it becomes clear to me that this must be part of a diff lock system which isn't included in the kit. When I compare the completed assembly to photos of ready made diffs with integral diff lock it seems I'm actually right

So finally my question, does anyone know how the diff lock supplied by any number of companies across the web actually works internally and more importantly to me can anyone point me in the direction of where I might get the additional parts rather that having to buy completely new axles?

The whole question runs to more traction on the first through diff as many of you seem to have suffered already. I don't really want to stuff the internals with play-doh, plasticine, etc. and don't want to have to buy more none matching diffs for the sake of one small feature.

I bit long and complicated but maybe someone could help please?

Thanks in advance


Mike

[djcrabtree]

Normally I would say just take one of the bevel gears and place it in between the other two. But seeing as this has 4 bevel gears I'm not 100% sure on this setup.