Someone in France, where I live, is selling a complete rear running gear from a 4WD Ford Sierra. (differential, driveshafts, and complete disc brakes)

I might be interested in purchasing it to fit on my Haynes Roadster this winter, but first, I have few questions for the Ford specialists on here please:

1 - On the add, it says that the rear diff is originally an LSD. Is that true? Did the Sierra 4x4 come with an OEM LSD?

2 - Do you guys know the ratio of the differential on a 4WD Sierra?

Thank you!

Yes lsd was fitted to most 4x4. Likely to be a 3.62 i think. But can vary on model and year.

[Edited on 21-10-17 by loggyboy]

Check the ID tag bolted to the diff , then check against the Sierra diff info sticky on this forum.

Dax (a uk kit supplier) used to make a Rush "Quadra" 4wd 7 type kit that used a Sierra 4x4 as the donor car. I don't know if the front and rear differentials were LSD or not though. I do know that the drivetrain added significant weight and complexity though. I'm also not sure that Dax even trade anymore either.

[Edited on 22/10/17 by nick205]

All 4x4 Ford Sierra’s has a Ford viscous LSD
Most were 7” & 3.62 the 2.0L 4x4 DOHC had the 3.9 LSD
The Cosworth Sierra’s had 7 1/2” 3.64
The later Sierra Sapphire had 7” 3.62

Mine was a xr4x4 2.0L. Came with 3.9 diff (lsd)

[Edited on 22/10/17 by Ben_Copeland]

Rear diff LSD 7" diff (dohc)
Front diff open
Center diff viscose 66/34 % F/R

2.9 / 2.8 v6 and cosi used 3.62 ratio, 2.0 dohc used 3.92 ratio.
rear suspension. with abs- disc brake, without abs- drum brake (but drive shafts bolt type)

[Edited on 22/10/17 by fregis]

Thank you very much for all the very useful answers! I've got the infos I needed.
It should be great that this dif for sale is a 3.92, as it is what I currently have on my car. But I have only small hopes as it looks to be very rare. I'm going to ask the owner.
Thanks again!