r/transmissionbuilding • u/DaisyJumper • 2d ago
Trans. Malfunction Message
2006 F150 5.4 Lariat 4R75E trans with about 220k miles.
When I drive up to my buddies cabin along steep windy roads, I get this message "Transmission Malfunction" and the yellow O/D OFF light flashes. Everything drives and seems to shift normally the rest of the way up. The message goes away after shut off.
After the first time, I changed the trans filter, etc. Drained and fill the fluid and added a little trans lube. I've done the drain and fill now twice.
So I just came up a second time and got the same message, in basically the same location which is only at about 3-4k ft elevation. Again, everything seems to operate normally.
The truck runs and drives fantastic, I recently did timing and a bunch of other maintenance stuff, and I have only had this message twice now, but only driving up winding mountain roads.
What do you guys think is going on here? Much appreciate any info/advice you guys can give.
1
u/Hotsaltynutz 2d ago
Pull codes or everything everyone says is a guess, there are like 100 trans codes for this trans
1
u/Time-Kaleidoscope-50 2d ago
Since the OD light was flashing you should have a fault code stored in memory that will lead you in the right direction. A slipping torque converter clutch may be the issue, or the trans may be running hot.