2019 with 6k miles hard Downshift

[CR Gittere]

So I was driving the truck today and was going down the freeway about 50mph or so and stomped on it to pass someone and the truck downshifted to 6th gear with a loud clunk and the traction light came one while I was accelerating and it did accelerate kind of slow...

Has anyone else seen this one?

 

[cayenne]

Sounds like the rear end got loose and TC did what it is supposed to do.

 

[FordTechOne]

That's the traction control intervening. The drivetrain thunk you heard was the tires breaking loose, its not hard to overwhelm the available traction when you have 510 lb-ft of torque. That's more than many diesels had in the early 2000's. As soon as TC is triggered, the PCM will cut timing and the ABS will apply the brakes. That's the loss of power you felt.