why do Renault espace with edc gearbox 1.6 diesel 160 horse power - fails

 (3) problème mélange d'eau et huile de boite vitesse automatique DW6 sur renault espace 5 - YouTube

they mix coolant and gearbox oil, therefore the engine do not get enough coolant. 

gearbox dw6 oil(6 speed edc gearbox): 7711579456

coolant anti freeze for renault espace 5: 7711428132 (glaceol rx type D)

Gearbox oil heat exchanger - oil cooler - 216058036R

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