I’ve got a 2017 F-150 King Ranch 5.0L with the 6R80 transmission, just shy of 100k miles. Had a pretty strange failure today and I’m curious if anyone has experienced something similar.
Was driving in traffic when the wrench light suddenly came on and the truck lost almost all ability to accelerate. Luckily, I was close to a parking lot.
The engine was still running, and I could feel the RPMs increasing when I pressed the accelerator, but the truck would only crawl along at maybe 5–10 mph regardless of throttle input. It almost felt like the transmission wasn’t transferring power, although I can’t say for certain.
I also noticed that the PRNDM21 gear indicator on the dash was no longer highlighting which gear I was in. All the letters were there, just no indication of the selected gear.
I managed to get parked, shut the truck off, and waited a few minutes. When I tried restarting, absolutely no luck.
Current symptoms:
Push-button ignition powers up the dash and electronics, but the engine won’t crank.
No engine response at all when attempting to start.
The wrench warning remains on with “See Manual.”
The gear indicator still doesn’t highlight Park, Neutral, or any other position.
The shifter physically moves between gears once the ignition is on.
I may have noticed a faint burning smell while limping into the parking lot, but I’m not 100% certain.
No obvious electrical issues, strange shifting, or other warning signs before this happened.
Here’s the interesting part: I had the transmission lead frame replaced by an independent transmission shop approximately 15k–20k miles ago because the truck was slipping between gears. It’s driven perfectly fine since that repair.
I had the truck flatbed-towed back to that same transmission shop tonight. They’ll take a look tomorrow.
I’m wondering whether this sounds like another lead-frame/range-sensor issue, a wiring or connector problem, a charging-system failure, or something more serious inside the transmission.
My two big questions:
Has anyone experienced this particular combination of symptoms, especially the missing gear indication followed by a no-crank condition? What ended up being the problem?
Is an independent transmission shop the right place to diagnose this, or does the combination of electrical and transmission symptoms suggest I should be taking it to a Ford dealer or a shop specializing in electrical diagnostics?
I’m hoping it’s something electrical rather than a cooked transmission, but I’m prepared for bad news.
Appreciate any thoughts, especially from Ford techs or anyone familiar with the 6R80.