Low Stall Speeds (Stall in Ranges 1-5). GMC Truck Yukon XL

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 2001 🢒 Yukon XL - 4WD 🢒 Transmission/Transaxle 🢒 Automatic Transmission - Allison 🢒 Low Stall Speeds (Stall in Ranges 1-5)

Problem

Action

Engine not performing efficiently.

Inspect for the following conditions:

•	Plugged or restricted injectors

•	High altitude conditions

•	Dirty air filters

•	Incorrect fuel/valve timing

•	Throttle linkage broken or not properly adjusted

•	Electronic engine controls condition

Refer to the Engine section of this manual.

The following specific sections should be helpful in defining the problem:

•	Refer to Diagnostic System Check - Engine Controls in Engine Controls - 6.6L.

•	Refer to Diagnostic System Check - Engine Controls in Engine Controls - 8.1L.

•	Refer to Symptoms - Engine Mechanical in Engine Mechanical - 6.6L.

•	Refer to Symptoms - Engine Mechanical in Engine Controls - 8.1L.

Stall speeds of 33% of normal implies freewheeling stator

Replace converter assembly. Refer to Torque Converter Replacement .

Engine smoke controls

Compare lugback to static stall speed.

Incorrect torque converter

Install correct torque converter. Refer to Torque Converter Replacement .