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4LHD/4LHDX Application Manual
Powertrain Control Solutions
REV 1.1
*W.O.T = Wide Open Throttle
1.3.4 Temperature Limitations
Functional Range:
-40˚C to 55˚C (-40˚F to 131˚F)
Defined as the ambient range where the vehicle will function without causing transmission operational concerns or thermal
distress in adequately cooled installations.
Underbody Temperature
Life of the transmission gaskets, seals and connectors is affected by elevated temperatures. Airflow around the
transmission and the proximity to heat sources such as catalytic converter or exhaust system influence the temperature
build up at the transmission surface. It should be noted that shift cable systems are also sensitive to heat, and should be
routed to avoid extreme temperatures.
Temperatures shall be monitored during testing to ensure appropriate temperature levels. A thermal packaging study is
recommended to verify all underbody temperatures.
Component Skin Temperature Limits
The following maximum temperatures are based on released component materials. These temperatures must not be
exceeded during test.
Exposed Area
Maximum Continuous
Maximum Excursion
External Seals
138°C (280°F)
150°C (302°F)
Oil Pan Gasket
138°C (280°F)
150°C (302°F)
Trans. Based on Non Metallic Connectors
138°C (280°F)
138°C (280°F)
Trans. Electrical Terminals
135°C (275°F)
135°C (275°F)
Trans. Wiring Harness
125°C (257°F)
125°C (257°F)
Controller (TCM)
105°C (221° F)
125°C (257°F)
* Reference Section 2.3 for cooler requirements and transmission sump operating temperatures.