Locked Diff on the rear vs "Active" Diff

[ongbenghui]

Hi,

Apologies as I am still new in Crawler.

I am looking at getting a Vaterra Twin Hammer, and as I was going through the online manual first. I noticed that the Rear Diff is a Locked Diff, vs a normal Active, moving Diff. Apologies for the term used.

Is there any reason why the rear need to be in locked mode ?

Is there a term for "Active" diff, does "Open" Diff means moving, working diff ?

Many thanks for any guidance.

[Mnster]

Traditionally crawlers diffs are locked to aid with traction.
A locked diff is a essentially a spool that ties the two axle shafts directly together.

The Active diff gives the vehicle a Open diff.
Not sure why it is called active? perhaps they consider that you can adjust the oil thickness to make it act more like a limited slip.

This video explains the types.
https://www.youtube.com/watch?v=gIGvhvOhLHU

Personally I would recommend locking it for rock crawling, backyard bashing or otherwise. Only time I would leave it open is on the track or street.

[ongbenghui]

Thanks for the note.

I will certainly like to use a Open Diff on the Rear with thick oil to control the "slip" given that I will likely to run it on a road surface as well.