Thread: Ashcroft ATB center diff mechanicals.

What do you mean?
As in how does it work?
It uses helical gears instead of bevel gears.
Think of the helical gears like springs, this is what turns(or not). Bevel gears are side cut(as in 90°) gears to each other like a crownwheel and pinion kind of thing.

You can't really see them(in the ATB unit) as the case is pretty much fully enclosed, but you see the 'pins' for each gear that does the 'diff' job.

Mine are 100klms away(still!) and I can't get to them(yet), otherwise I'd get a photo of one for 'ya.

if you check Youtube for Torsen type diff, the animations you find on those sites show you how they work. ATB is a Torsen type diff, that is just not called Torsen(trademark name or something like that)

Are you looking for axle diffs or centre? .. or all three?

Just to add, it's like a Type II Torsen or Quaife ATB, not a Type I Torsen.
It's function is identical to the rear and front diff Ashcroft ATB's.

And lubricant type makes a fair old difference on performance.
You really need a fluid without any LSD active at all, or they don't work properly.
Manual Trans/transaxle fluids seem to work nicely.

Thanks, type II Torsen.
As for getting them, one day, one day. I was just curious as to what type it was.

Originally Posted by rick130

....
Manual Trans/transaxle fluids seem to work nicely.

I was thinking Pentrite synth gear oil for when I eventually get mine back.

I got mine up at my mechanic doing the diff install .. I then bring them home and install them into axle.
I think I'm too clumsy to install diffs into final drives and get everything spot on enough.

Lack of work .. COVID .. then lack of work again has turned my ATB wish into a 2 year ordeal now!

Originally Posted by AK83

I was thinking Pentrite synth gear oil for when I eventually get mine back.

I got mine up at my mechanic doing the diff install .. I then bring them home and install them into axle.
I think I'm too clumsy to install diffs into final drives and get everything spot on enough.

Lack of work .. COVID .. then lack of work again has turned my ATB wish into a 2 year ordeal now!

The Progear full syn diff fluid has LSD additive, IIRC the semi-synth GL5 is LSD additive free

I run the trans gear from penrite in my Lt230 with the atb has no lsd additives

Originally Posted by rick130

The Progear full syn diff fluid has LSD additive ..

OK thanks. Info I will eventually need.
Only problem is I'll probably forget it in a few years time when I may get the chance to get them back to finally install them!

.... damned COVID!

Originally Posted by AK83

OK thanks. Info I will eventually need.
Only problem is I'll probably forget it in a few years time when I may get the chance to get them back to finally install them!

.... damned COVID!