Doublerô Quick Facts and FAQ answers
reduction of NP203 gearbox: 2.01:1
Gear reduction of NP205: 1.96:1
Gear Ratio of combined transfer cases: 3.94 (basically 4:1)
Overall Length of assembled 203 with NP205: 21.5" from front of
203 to ujoint center
Overall weight of Doublerô assembled with 203 and 205:
Weight of Doublerô kit: 24#
The lowest point on the NP203 is about 8.5" below the drivetrain
centerline. The NP205 is easily rotated to match.
transfer case was used in GM, Ford and Dodge trucks behind these
TH350, TH400, SM465
The NP203 gearbox is adaptable to many other transmissions but
can use a factory adapter with the above mentioned
If you have a
Ford front axle (or other application with the differential on
the driver side) you need to use a Ford NP205. If you have a GM
front axle (or other application with the differential on the
passenger side), you need to use a GM NP205. The 203 and 205 do
not need to be the same brand, we can mix and match to suit the
parts you want to use.
or Dodge Doublerô kit requires a 32 spline input NP205 which came in GM
trucks with a TH400 transmission. Your first choice is a TH400
version from '84 and older. This will have a short 32
spline input and a figure 8 bolt pattern. 2nd choice is a
205 from '85-up that will require a short 32 spline input swap
since the input is too long. We also have a
conversion kit to turn other versions of the NP205 into a 32 spline input
with a little more work involved.
applications will use any married ford NP205. All Ford married
205's came with a 31 spline female input gear. No modifications
to this case are required.
dual crossmembers for mounting the Doubler system. You can use
lightly modified factory crossmembers for many applications or
click here for some
ideas on custom high clearance mounting.