Sierra 4 x 4 front diff drawing.

[mickrick]

Hi, would anyone happen to know where I may find a dimensional drawing of the front Sierra 4 x 4 diff? I'm particularly interested in the dimension between the pinnion gear shaft and crownwheel centers. To clarify, the offset of the pinion shaft from the crownwheel center. TIA

[sortedcossie]

I've just checked the workshop manual for 4x4 and Escort Cosworth, which use the same diff - no measurements though. Best be might be to contact one of the firms that do uprated parts for them for rally purposes.

[mickrick]

Thanks for checking for me.
Believe it or not, it's actually for a boat bow thruster I'm working on....
The internals are Sierra parts. 3.91 crown wheel and pinion.
The folks who I'm doing the work for have CNC machined a billet casing from a scan of the old broken part, which is NLA, and the gears aren't quite meshing right. It's ran for three years since the last time I put it together, but we're trying to fettle it a bit more.

[Billybob_55]

I have a front diff in garage going spare along with the gearbox from a Sierra 4x4

Edited by Billybob_55 on Friday 14th March 17:01

[mickrick]

Billybob_55 said:

I have a front diff in garage going spare along with the gearbox from a Sierra 4x4

Edited by Billybob_55 on Friday 14th March 17:01

Thanks for your response All sorted now. It turns out it was a rear diff! They brought us the case, and I see straight away it was a rear, not the front as I was told.
The answer is 1 1/4".