DeVille V8-4.6L VIN Y (1998)
CAUSE
Important: Prior to performing any mechanical repair, it is imperative to confirm that the output speed sensor circuit is functioning normally and that
the condition is not a malfunction in the speed sensor or cruise control system or wiring. Specifically, inspect the wiring harness connector at the vehicle
speed sensor. The vehicle harness may be installed such that the harness exhibits excessive tension, causing a poor connection at the vehicle speed
sensor.
This condition may also be caused by air gap variation between the speed sensor (130) and the differential carrier (110) due to movement of the final
drive internal gear (120) relative to the transmission case. This causes wear of the bushing (124) in the case extension (134). Some affected transmissions
may have a mis-machined final drive internal gear outside diameter and has a final drive internal gear retaining ring (135A) with a corner break at the
thickest side. Some vehicles with the 3.11 or the 3.71 final drive ratio carrier assembly (100) may also have one or more planet pinions (103) with
mis-machined gear teeth.