English to French Tech/Engineering Engineering: Industrial Grue

Contexte : Manuel d'une grue

"Dump Switch

Up shifting to the next gear (travel speed) may be done at any engine speed, while the crane is in motion, but first ease up on the accelerator pedal and press and hold the dump switch.

ATTENTION

Do not shift the transmission to the next gear without first pressing and holding the dump switch. Serious damage to the transmission could occur."

J'ai bien trouvé (Termium, GDT) "sélecteur vide-vite" mais dans le contexte du transport aérien... forcément... :s

Merci d'avance et bon week end à tous :)
Mathieu