08 duramax 6.6 allison trans calls for 7.4 qts drain
and fill i replaced trans lines after they blew off
while driving and replaced trans cooler have about
10qts in it and still reads on cold part of dipstick
Make sure it is all warmed up, taking it for a ride, or just shifting it threw the gears with foot on the brake, checking the fluid level. Keep checking and adding fluid if necessary until full.
The 7.4 quarts is for a normal drain and re-fill. Blowing the lines off may have allowed the transmission pump to pump out fluid from the torque converter as well which would result in needing more ATF.
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