This Preliminary Information communication provides information to the technician the steps to diagnose and repair vehicles that have rough, harsh, or stiff ride. The concern is most noticeable between 35-55 mph on fairly smooth roads, when coming in contact with small road imperfections, or expansion joints. Technician will need to use the vibration analyzer CH-51450-A (Pico Oscilloscope), while driving the vehicle in 35-55 mph range on the same section of road for each stage of evaluation. If a rough, harsh, stiff ride has been determined to be the customer?s concern following evaluation using the Pico scope, then replace the complete front suspension shock with coil spring assemblies, and rear shocks with updated parts and reprogram the Suspension Control Module (K19) with updated calibrations available in TIS2WEB.
