Behemoth Drivetrain Strong Box

[Ghost]

Yes. It's a 1/4" plate that mounts between the Black Box and the transfer case. I think part of our issue is that we were mounting to a 241OR, as opposed to a 231. Even though Black Box said it would mount, the opening in the mount was not large enough to clear the 241OR. We ended up cutting a new mount from scratch.

There were also some issue with the length of the studs that were shipped with the Black Box, but that was solved with different studs.

I will say the box shifts easily, and having 2.72:1 low in 2WD is quite handy.

David Bricker / SYR

What did you use as the donor gears? Or did you just buy it all form them? I have a couple 231's from xj's laying around but from what I have ready they recommend the 6 planetary gear set. I have not researched that yet.

 

[David_Bricker]

What did you use as the donor gears? Or did you just buy it all form them? I have a couple 231's from xj's laying around but from what I have ready they recommend the 6 planetary gear set. I have not researched that yet.

Black Box comes as a fully assembled unit. There are no other parts to get. It includes the fully assembled underdrive, cable shifter assembly, mounting foot, and mounting studs. My understanding is they use a 6 gear planetary, which may be for a 241 2:7:1 ratio. All parts are new - there are no reused parts, and no reuse of cases, etc.

David Bricker / SYR

 

[souske]

I know when i swapped in my 241OR, i had to trim quite a bit of that foot to get it to clear

 

[Mnkyboy]

When I built the Behemoth I put in a 3 pinion planetary but I put a wide chain and 6 pinion planetary set in the 231J that went behind it.

I got the planetary out of an 89 231C.

 

[BRIANHO13]

The 231-300 doubler I ran only had the 3 planetary gears in it and it has blown up several dana 300's with no issues.

 

[Ghost]

Black Box comes as a fully assembled unit. There are no other parts to get. It includes the fully assembled underdrive, cable shifter assembly, mounting foot, and mounting studs. My understanding is they use a 6 gear planetary, which may be for a 241 2:7:1 ratio. All parts are new - there are no reused parts, and no reuse of cases, etc.

David Bricker / SYR

Ok I must have in confused. I thought I read that it came as a kit too.

The 231-300 doubler I ran only had the 3 planetary gears in it and it has blown up several dana 300's with no issues.

Yea I was actually chatting with Jim about that recently. My only beef with my set up is the not so low lowrange and the tires not sticking to rocks as well as I want. Hopefully I can get in the shop soon and check my engine out.

 

[CarolinaCrawler]

If I were in the market for a under drive box i would go with NWF eco box. Its a DIY kit from a reputable company. I think its by far the best way to go.

http://www.northwestfab.com/NWF-Eco-Box-Billet-Planetary-Doubler-Case_p_2403.html

 

[Ghost]

If I were in the market for a under drive box i would go with NWF eco box. Its a DIY kit from a reputable company. I think its by far the best way to go.

http://www.northwestfab.com/NWF-Eco-Box-Billet-Planetary-Doubler-Case_p_2403.html

This is actually what I am looking at doing. I'm looking for the 231/241 parts atm. I have a couple broken ones now but they are all the older 3 planetary style. I'd like to find a broken unit with the 6 planetary unit cheap.