Driveline Clunk When Shifting R-to-D - Transmission Fluid Service with Seafoam TransTune

Transmissionintermediate✓ OP Confirmed

Problem

Clunking noise from the driveline area when shifting between Reverse and Drive, and just before coming to a complete stop during deceleration. The noise was not present during normal driving or steady acceleration.

Clunk noise when shifting from Reverse to Drive or Drive to ReverseClunk just before coming to a full stop, especially from higher speedsNoticeable play in transmission output shaft (~4-5mm)Slight play in rear differential (~3mm)Occasional slight clunk during hard accelerationRough shifting while driving

Root Cause

Old, degraded automatic transmission fluid that had never been changed despite approximately 130,000 miles of primarily city driving. The worn fluid caused rough internal shifting behavior and contributed to the clunking felt through the driveline.

Confidence

Low confidence — Original poster confirmed this resolved the issue

View Original Thread →Posted May 2024 on SupraForums.com