High speed slamming into lower gear

[Flash1034]

On a recent road trip, I had two occasions where I was driving at freeway speeds and when I put the hammer down to pass someone the transmission would slam down to a lower gear so hard it felt like I was going to leave my drivetrain on the freeway. It only happens rarely. I’ve checked transmission fluid level and it’s good. The truck only has 18k on it. Any ideas? Anybody else experienced this?


Thanks.

 

[FordTechOne]

What year and build date is the truck?

 

[Flash1034]

April 2019

 

[FordTechOne]

April 2019

There are no service messages for that build date, is the truck completely stock? If so you may need to bring it into the dealer for diagnosis.

 

[Antho]

I had this happen a few times when i was in adaptive cruise control. I would accelerate to pass and it would slam like you described. Happened twice on a road trip. Only time I've ever had it happen.
I had the traction control and abs I Neil e pop up momentarily. 2019

 

[BIGDJE]

i also have 19 and has happened 5 or more times its so hard i thought someone rear end me

its very random can go months without it happening

 

[Turning Blue]

Same here, 2019, happened once on a road trip. I'm not quite sure what happened? But it was very abrupt! I think I had my adaptive cruise on too, and when I accelerated it happened. I think my traction control light even flashed. I've never had it happen since, and can't replicate it...not that I would want to.

 

[Flash1034]

Yep, it feels like someone just plowed into you. You’re right about the traction control light. Mine flashed a few times as well. Sure would like to figure out how to fix it so this never happens again. It can’t be good for the truck.

 

[Turning Blue]

My best recollection is it happened as I applied heavy acceleration in heavy traffic with 3 or more lanes. I was wondering if the collision avoidance didn't like that I was accelerating aggressively while closing in on another vehicle I was going to go around?

It has never happened during less aggressive driving.

Maybe we should call ourselves the 2019 Acceleration Club?

By the posts so far, @BIGDJE should be the President of our club...lol.

 

[Donovan]

I had this same thing in my 2017. The stealership performed the TSB and now its buttery smooth.

Garlic Butter.