No Second and Sixth Gear

WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.

Checks	Causes
2 - 6 Clutch Assembly	Inspect for damaged or worn 2 - 6 Clutch Plates (540 - 542). Inspect for damaged, worn, broken, improper surface finish or sheared splines on the Low-Reverse Clutch Assembly (543). Inspect for damaged or broken 2 - 6 Clutch Piston (535) and piston seals damaged, worn or delaminating. Inspect for broken or binding 2 - 6 clutch Piston Return Spring (536).
Reaction Carrier Assembly (567)	Inspect for stripped or sheared splines on the Input Ring Gear. Inspect for disengaged or broken Input Ring Gear Retainer.
Reaction Sun Gear Assembly (566)	Inspect for damaged or broken Reaction Sun Gear Assembly hub. Inspect for damaged or broken sun gear weld. Inspect for loose or worn Reaction Sun Gear Assembly bushing.
Case Assembly (50)	Inspect for stripped or sheared splines. Inspect for broken or disengaged 2 - 6 Clutch Piston Return Spring Retainer (537). Inspect for damaged, worn, or improper surface finish in the piston bore.
Output Carrier Assembly (574)	Inspect for reaction ring gear damage or missing ring gear snap ring.
Control Valve Body Assembly	Inspect 2-6 Clutch Regulator Valve (419) for debris and stickyness.
Control Solenoid (w/Body and TCM) Valve Assembly	Check 2-6 PC Solenoid 4 for proper operation. Refer to Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test .