Pinpoint Test N: Other Concerns

• Positive drag or rocking sensation at start up while in Park 
  • The 10R80 applies three clutches in Park in anticipation of Reverse or Drive engagement. Each clutch application creates a small positive drag to the driveline and could cause a slight rocking sensation of the vehicle at or just after engine start in park. This is a normal and desired behavior of the 10R80 transmission.

• Assembly gel present in transmission cooler case ports and/or main control assembly on new or low mileage transmissions 
  • A clear gel-like grease is injected into the transmission case cooler ports before the transmission is shipped from the assembly plant. If enough grease is injected, it may be pushed back into the main control. The grease acts as a plug to prevent leaks during transmission installation into the vehicle. Grease found in the cooler ports and/or main control in new transmission assemblies is normal and has no affect on performance. As the transmission gets up to operating temperature, the grease will melt and dissolve into the transmission fluid.

• Selector lever high effort 
  • See selector lever binding or difficult to move - requires excessive effort condition. REFER to: External Controls - Vehicles With: Column Shift . REFER to: External Controls - Vehicles With: Console Shift .

• No start - transmission range indicates Reverse when the selector lever is in Park 
  • See selector lever linkage is out of correct gear relationship condition. REFER to: External Controls - Vehicles With: Column Shift . REFER to: External Controls - Vehicles With: Console Shift .

Possible Sources 

• Normal operation
• Transmission external controls

Diagnostic steps are not provided for this symptom or DTC. REFER to: Diagnostic Methods