4L80E 4WD to NP205 CIR 6 Long Input Adapter

The Advance Adapter 50-6912 is a spacer adapter engineered for the specific task of mating a GM 4L80E 4WD transmission to the 1985-91 GM NP205 transfer case, provided the NP205 has a long input gear measuring 3.50 inches. This adapter is 2.125 inches in length and features a 6-bolt circular mounting pattern. A key feature is the integrated vehicle speed sensor (VSS). This is crucial because GM 4L80E transmissions rely on both input and output shaft speed sensors for proper computer operation. Older 4WD transmissions (up to 1996) and all 2WD transmissions generally have a rear reluctor ring. However, 1997 and newer 4WD 4L80E transmissions often omit this ring, making replacement costly. The included VSS in this adapter kit serves as a functional replacement for the transmission's output shaft speed sensor, ensuring accurate data for the vehicle's computer. It is important to note that this kit does not include a shifter bracket for the NP205 shifter, requiring the user to fabricate a linkage bracket. Furthermore, this adapter kit mandates the use of a 4WD 4L80E transmission that retains its factory 4WD tail housing.