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Behemoth Drivetrain - Strong Box Underdrive

Behemoth DT

New Member
Joined
Jul 19, 2011
Messages
14
Loc.
Clarkson, KY
STRONG BOX KITS: At this time, we have kits for full size Ford transmissions, full size Chevy transmissions, S10/Blazer transmissions, and Ranger/Explorer transmissions; using BW1356, BW1354, NP271, and NP231/241 planetary gears, including their electric shift versions. Jeep kits are also available using the NP231/241 planetary gears.

Our ultimate goal is to offer kits that will work with the planetary gears that are readily available to you; saving you time and money otherwise spent looking for that one manual shift case that might work with other kits.



STRONG BOX FEATURES: •~2.4:1 - ~2.7:1 Low range multiplier (ratio varies slightly depending on which planetary set you use as a donor)

•Low profile design minimizes / eliminates fitment issues with floorboards, exhaust, front driveshaft, shifters, etc...

•72 position, 360º clockability in 5º increments

•New 4340 chromo output shaft thru hardened

•6061 billet aluminum housings precision machined

•Fill plug, drain plug, vent, and particle magnet

•Cable shifter available

•Easy installation: No machining, or welding required

•Adjustable shift detent pressure

•Clocking options for shift mechanism

All of our Strong Box kits use durable planetary gears with 2.4:1 - 2.7:1 low range gearing. We can use planetary gears from electric shift transfer cases that you otherwise may be throwing in the junk pile.

These kits are designed to be compatable with many different transfer cases, including the NP 205 transfer case, and allow use of the original NP 205 shift rails with little to no modification, even with most "twin stick" conversions.



The Strong Box is 7.95" diameter, and will range from 7" long to 8.25" long, depending on the choice of planetary gears used.

If you ever need to clock the trasfer case in a different position, you remove 6 bolts, rotate the transfer case to the desired alignment, replace 6 bolts. No need to drain, or scrape RTV, due to it's completely sealed design.



What transfer cases can be bolted to the back of the Strong Box?



We have versions that are compatable with the following:

•Virtually any 6 bolt pattern transfer case.

•Figure 8 NP205 (with the proper input shaft; we have several available)

•5 bolt pattern mini-truck (S-10, Ranger, Explorer)

• A divorced version of the Strong Box will be available soon!

figure8strongbox1_zpsfcd89062.png


(NP231/figure 8 NP205 Strong Box)

Shaftandbearing_zps8c008d3f.png



StrongBoxmount1_zpsba6a7c8c.png


(BW1354/1354 Strong Box with optional mount)




/\ Transmission mating end of empty Strong Box DIY kit.



/\ Transfer case mating end of Strong Box DIY kit, with output shaft installed.





GET ONE BEFORE THE PRICE GOES UP IN February 2014!!



DIY KITS NOW AVAILABLE FOR THE FOLLOWING:



BW1350

BW1354

BW4405

BW1356

NP231

NP241

NP271

.... AND THIER ELECTRIC SHIFT VERSIONS ALSO.



You remove the planetary gears from a donor transfer case and install into the Strong Box housing in the same manner.

$599 + $35 USA shipping (We do ship internationally; Contact us for details)

To place an order, send us a PM of what you want, and we will email an itemized invoice that you can pay either through Paypal, or your Credit Card Company.

We do build complete units also. Contact us for more information.

Thanks for the orders so far!
 
OP
OP
Behemoth DT

Behemoth DT

New Member
Joined
Jul 19, 2011
Messages
14
Loc.
Clarkson, KY
We have designed and are currently prototyping a Strong Box just for the EB Dana 20 guys.
With our kit you end up with a 28 spline input Strong Box that has a 2.46:1 low range. The output of this Strong Box will replace the input of the Dana 20 with our thru hardened 4340 shaft. The kit can be had in an empty DIY case which you would load BW1354 (Ranger/ Explorer) gears into for $699, or you can get it assembled complete with gears for $300 more. This kit is 4.5" long, and will bolt up and spline directly to your stock EB 28 spline 4x4 transmissions extension housing.

As usual you will have tons of options for clocking, and were working on a rear mount for the D20 as well.

We can do the same kit to a Dana 300.

We can easily make the 28 spline Strong Box to go to a NP205, or other transfer case, but it would be 6.9" long, since it would require the Standard male - female spline output/input connection.

We will have some production pics in a week or so. We are currently completing orders, but we're excited to see this one come to life! If you have an EB and want more torque, we have the best bang for your buck by far.
 

stlo

Bronco Guru
Joined
Mar 1, 2011
Messages
1,228
Loc.
tulsa
Looking forward to the pics..and mating of the dana 20..... Had my eye on these for awhile but no bronco support .......look forward to it.....thanks
 

JSmall

Bronco Guru
Joined
Feb 18, 2004
Messages
3,223
This looks interesting. I would like to see the D20 version. Could this be made to work with a 31 spline zf trans?
 
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OP
Behemoth DT

Behemoth DT

New Member
Joined
Jul 19, 2011
Messages
14
Loc.
Clarkson, KY
Im anxious to get it picture worthy myself! We want to make sure to take care of our current orders first.
As for the 31 spline input we have been doing those for quite a while now using the BW 1356 planetary. Very strong gear set.
 

JSmall

Bronco Guru
Joined
Feb 18, 2004
Messages
3,223
Im anxious to get it picture worthy myself! We want to make sure to take care of our current orders first.
As for the 31 spline input we have been doing those for quite a while now using the BW 1356 planetary. Very strong gear set.

I'll send you an email. Thanks
 

KyleQ

Bronco Guru
Joined
Apr 24, 2008
Messages
5,480
Love the idea, machine work looks good - your history on Pirate has me worried though...
 
OP
OP
Behemoth DT

Behemoth DT

New Member
Joined
Jul 19, 2011
Messages
14
Loc.
Clarkson, KY
Here's a look at the new 231/D300 Strong Box Shorty. The EB D20 kit is nearly identical.
Splining shafts for them starting tomorrow.




We will be picking up our "new" CNC machine in the next week or so, and it will triple our production.
Let us know if you have any questions.
 
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OP
Behemoth DT

Behemoth DT

New Member
Joined
Jul 19, 2011
Messages
14
Loc.
Clarkson, KY
Can you build the strong box with 231/241 planetaries to fit behind the C6 with 31 spline output?

Yes. There is an extra $150 for the 31 spline input shaft.

If you use the BW1356 gears and going to a Dana 20 or Dana 300, you will get the 31 spline input also. 1356 Shorty kit is 6.5" long.
 
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Behemoth DT

Behemoth DT

New Member
Joined
Jul 19, 2011
Messages
14
Loc.
Clarkson, KY
what is the shortest length box you make to go between my 4R70W and my np205?

Right now it is 7.9" using 241/271 gears, or 8.25" using Bw1356 gears. We can also do a 7.9" Strong Box with BW4406 gears (97+).

We are working on a version that replaces the 205 input shaft. When we get that going (6 months +) they will be 5.25" for the 241/271, and 6.5" for the bw1356. And they will cost 30-50% more.
 

SpareParts

Bronco Guru
Joined
Nov 13, 2004
Messages
5,592
I've talked to you a couple times in the past, I'm interested in the 1356/205 range box. I'll report back here when the deal is done!
 

SpareParts

Bronco Guru
Joined
Nov 13, 2004
Messages
5,592
Ordered mine today!! I'll post pics in my build thread and a couple on here as I get them, 1356 to 205 for me.
 

gearbox

New Member
Joined
Dec 9, 2003
Messages
6
Loc.
Acton, Ca
Roger teno acton, ca
818-636-4239
just spoke to you about a strong box for a Dana 20 in the old Bronco 1974 and would like to know when they're available and get one ordered from you possibly
you asked me to send you a message so here it is
thanks for your help
 

bronjeep

New Member
Joined
Apr 14, 2014
Messages
2
Loc.
Quebec, Canada
I should receive my gear box soon to adapt my C4 to Dana 20. First experience for them, I'll be the first one to use it he said. I hope he knows what he is doing. I still have confidence...:)
 
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