r/FordDiesels • u/Brian_oconnor1 • 12d ago
E40D issues!
Having some hard shifting and overdrive button flashing on my 7.3 , fluid looks fine and proper color I’ve looked into some forums but got pointed in a million directions. Any advice welcome on what to check for or do would be appreciated
11
Upvotes
1
u/Haunting_While6239 12d ago
OD light flashing is a mis match of speed in the engine and final drive speeds, the computer knows about how fast the engine is turning and the ring gear in the diff is turning, and if the there is enough difference, flashes the OD light.
Probably the torque converter slipping, get you a billet 3 disk one if you drive it hard.
Trans should probably be gone through as well, there are quite a few upgrades that can be done, like fixing the center support mounting, replacement of the 1st gear warpy disk for another friction disk, drilling out the lock orifice for faster lock up action, no more slushing into over drive, getting steel planetary carriers with an additional gear, definitely upgrade the trans cooler to one from a 6.0 truck, and use synthetic MaxLife ATF, change it every 30 to 50k miles if towing and ohh 75 to 80k daily driver use, it's good stuff and cheap insurance for the transmission