gf2755p2000aea

Transmission oil cooling, function

Type gf · topic 27.55 · version 0100 · 2008-05-28

Applies to: TRANSMISSION 722.800 in MODEL 169.0 /3, 245.2 as of Model Year 09 /YoM 08 model refinement package except CODE (581) Automatic air conditioning TRANSMISSION 722.801 in MODEL 169.0 /3, 245.2 as of Model Year 09 /YoM 08 model refinement package except CODE (581) Automatic air conditioning TRANSMISSION 722.800 in MODEL 169.006 /007 /008 /306 /307 /308, 245.207 /208 as of Model Year 09 /YoM 08 model refinement package with CODE (581) Automatic air conditioning TRANSMISSION 722.801 in MODEL 169.031 /03

Where it sits

Function group 2 Chassis › 27 Automatic transmission › 27.55 Transmission-oil cooling — Series 169 (models 0**, 006, 007, 008, 031, 032, 033, 034, 3**, 306, 307, 308, 331, 332, 333, 334) · Series 245 (models 2**, 207, 208, 231, 232, 233, 234)

Also applies to engines/gearboxes: 722 800, 722 801

GF27.55-P-2000AEA

Transmission oil cooling, function

7.5.08

TRANSMISSION 722.800 in MODEL 169.0 /3, 245.2
as of Model Year 09 /YoM 08 model refinement package
except CODE (581) Automatic air conditioning

TRANSMISSION 722.801 in MODEL 169.0 /3, 245.2
as of Model Year 09 /YoM 08 model refinement package
except CODE (581) Automatic air conditioning

TRANSMISSION 722.800 in MODEL 169.006 /007 /008 /306 /307 /308, 245.207 /208
as of Model Year 09 /YoM 08 model refinement package
with CODE (581) Automatic air conditioning

TRANSMISSION 722.801 in MODEL 169.031 /032 /033 /034 /331 /332 /333 /334, 245.231 /232 /233 /234
as of Model Year 09 /YoM 08 model refinement package
with CODE (581) Automatic air conditioning

Function requirements for transmission oil cooling, general

Circuit 87 ON

Circuit 61 (engine running)

Transmission oil cooling, general

In order to reach the operating temperature of the transmission more quickly, the transmission oil is heated by the engine cooling circuit.

Transmission oil cooling lowers the temperature of the transmission oil and thus prevents overheating damage in the transmission.

Transmission oil cooling, function sequence

The transmission oil is drawn out of the transmission oil pan by a mechanical pump in the transmission and pumped via the feed to the transmission oil heat exchanger (which is integrated in the engine radiator). Then the transmission oil flows from the transmission oil heat exchanger to the transmission oil thermostat. At a transmission oil temperature <90 °C, the transmission oil thermostat directs the transmission oil back to the transmission via the return.

At a transmission oil temperature >90 °C, the transmission oil thermostat opens and the transmission oil flows through the transmission oil cooler, before it flows back through the return to the transmission.