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dana 20 in doubler questions

patford

New Member
Joined
Dec 12, 2010
Messages
28
truck is set up with zf 5 speed and 205 need more gearing for crawling . Have dana 20 t thinking of putting it behind a black box , trying to keep thing short as possible . i know about needing to up grade the output shaft but what are other problems ?
 

garberz

Bronco Influencer
Joined
Jun 24, 2007
Messages
6,856
Loc.
Conejo Valley, Ca.
Why not put the 205 behind a Black Box? It would be a lot stronger than doubling a 20. Length will be an issue no matter what doubler you use.

Mark
 

nvrstuk

Contributor
Just a Bronco driver for over 50 yrs!
Joined
Jul 31, 2001
Messages
8,615
Other problems...lol....

-output shaft a must

- cases crack ...I went through 4

- low range gear set teeth tend to peel off...yeah just idling


Don't put a D20 behind a doubler...I ran one from 99 through 2011 behind a 351/ZF/NP203 ...

I upgraded and have never had an issue since the upgrade to a 418/ 4r70WluneV/ Atlas. I have since replaced the Atlas with the 205...perfect upgrade...

Nothing worse than driving a thousand miles to go to Moab or ? and break your D20...

Totally preventable with an Atlas or 205.

The Black box or 203 is perfect with the 205. Do the math as an Atlas 4.3 behind a 203 at almost 2:1 is too low for 99.5% of wheeling.

Do NOT believe anybody that says the 205 is too big, won't fit between the frame rails, is old.(well,true but any part you want is available), isn't as strong (rated at 10,000 ft lbs torque input, weighs too much...all bogus myths.

I weighed the 205 and the Atlas...less than 18lbs difference to save $2000...worth it for me.
My 205 behind my Klune is actually an shorter than the Atlas behind the KluneV with the same spacer.

Hope this helps some
 
Last edited:

ScanmanSteven

Bronco Guru
Joined
Dec 19, 2010
Messages
1,129
X2 on the 205, if you don’t want to break pair the 205 with some of the offerings, Klune, Behemoth (my choice) or Blackbox, also a good choice.
 
OP
OP
P

patford

New Member
Joined
Dec 12, 2010
Messages
28
Only reason to look at the 20 is about 3 inches shorter mild power 302 and only 33 tall tires .Any pics of your doubler set ups?
 

nvrstuk

Contributor
Just a Bronco driver for over 50 yrs!
Joined
Jul 31, 2001
Messages
8,615
I think the 205 is appr.12.5" long...if have to look at my build list specs (or look on the Net). D20 is appt 10.5" long

Key here is the doublers are actually shorter than just the B ronco adapter housing.

Bronco adapter housing is 9 3/8 and most doublers are 6to 8" long.
 

nvrstuk

Contributor
Just a Bronco driver for over 50 yrs!
Joined
Jul 31, 2001
Messages
8,615
Here's a couple of KluneV (planetary 2.72:1)
 

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nvrstuk

Contributor
Just a Bronco driver for over 50 yrs!
Joined
Jul 31, 2001
Messages
8,615
Pic from the rear...more pics in my build thread below but it would take some searching.

The lowest point of the 205 is 1 1/2" above the radius arm bracket. At one point I had it 1" above the bottom of the frame rails but at full susp. droop I was maxing out ujoint angles even running a HP60 up front with caster/knuckle correction and with a TruHi9 in the rear...so I had to lower the T-case down a couple inches...
 

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