Just bought a new to me truck. 99 peterbilt 379. C12 Cat. Eaton 10 spd. The Jake brakes cut out while down shifting but only in 7th gear and only between 1200 and 1000 rpm’s.
Happens every time. It will Jake brake the whole range of rpm’s in every other gear but 7th. Local shop is baffled.
C12 Jake brake cuts out in 7th gear
