Depending upon the year and transmission, Ford New Venture NV271F manual shift transfer cases will have one of three Input Shaft choices. 31 Spline input shafts were used for 1999-2004 models with 4 speed automatic transmissions and 1999-2002 trucks with ZF5-47 5 speed manual transmissions. 2003 and 2004 applications are not so cut and dried because Ford VIN based parts lookup usually shows the 31 spline input being used with 5R110W 5 speed automatics behind Diesel and V10 engines, but the transfer case assemblies listed for the same vehicles have 34 spline input shafts. A 24 spline input will be found on 1999-2002 transfer cases in V10 or Diesel trucks with ZF 6 speed manual transmissions. For the 2003 model year, the 24 spline 6 speed input shaft was replaced by a 34 spline input shaft. The 34 spline input is used on all 2005-2010 Super Duty models with all engine and transmission combinations.
The non-rebuildable Planetary Assembly has 6 needle bearing supported pinion gears that are driven by the input shaft to provide low range gearing for the NV271F Transfer Case. In most cases, the Planetary Assembly will never need replacement, but the 34 small needle bearings under each pinion gear and the pinion gear teeth themselves are prone to damage from from lack of lubrication/dirty oil and from metal chips that may occur under high wear situations. The two Planetary Thrust Washers and the Snap Ring should be replaced any time you perform major transfer case service. The Planetary Annulus Gear, which is the big gear pressed in the front case into which the Planetary Assembly fits, is only sold as part of the Front Case Half.
