Slipping or No Third Gear

WARNING: This page is about a different car, the 2004 Pontiac Aztek and 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.

Checks	Cause
DEFINITION: A large engine RPM increase is noted in third gear, Drive range, with little or no vehicle forward speed increase. First, second, and fourth gear operation are normal. Shifts into third gear are soft or do not occur. Third gear ratio is 1.000:1.
Automatic Transmission Fluid Level	Low fluid level
Transmission Main Line Pressure	Low transmission main line pressure
Oil Filter Assembly	The oil filter assembly (100) is missing, plugged, or damaged. The oil filter seal assembly (101) is missing or is damaged.
Control Valve Body Assembly	The 2-3 shift valve (357) or the 3-2 manual downshift valve (356) is stuck or binding. Debris is found in the passages of the control valve body (301) or of the control valve body spacer plate and gasket assembly (396) The #4 or the #9 ball check valve is missing or mislocated.
Driven Sprocket Support Assembly	A plugged third clutch oil passage in the driven sprocket support assembly (609)
Third Clutch Assembly	Input clutch housing oil seal rings (628) are missing or damaged. The third clutch ball check valve assembly (724) is missing or damaged. The third clutch piston (642) is damaged. The third clutch piston inner seal (641) is missing or damaged. The third clutch plates (645-648) are worn or misassembled.
Third Clutch Sprag Assembly	The sprag (720) was misassembled or backwards on the inner race (661). A damaged third clutch sprag assembly (653, 661, 719-721)