I am going to try and post a video to go with this post. I have a 2018 f150 xlt with the 5.0, 10 speed. I have 2 main problems that i cannot get fixed.

1. When the temp gets below 50 at night and i come out to leave in the truck. The first 1 to 2 cycles through of the transmission are ROUGH, slips it’s way through most of the gears and revs up super high before slamming into gear. I have found that if i let the truck warm slightly it fixes most of this issue, but am i stuck with this for good????

2. the more annoying out of the 2. The dreaded rattle. Upon acceleration and as i give the truck gas it sounds like a rattle under the hood, can even take the form of a knock from time to time. When i get to a reasonable speed, about 45 or 50, it seems to get better but i can still hear it when listening. Nothing seems to be loose but I’m at a loss. Can anyone help or throw out any suggestions on what to try??

 

I can't help you much with number 1 - transmissions aren't my gig.

number 2 though I have a couple questions.
1) does this rattle occur on accel only or on decel as well. Does it happen on cold start?
2) Reasonable speed aside, does it get better as temp increases?
3) have you had the ECU / PCM reprogrammed by Ford in the last year or two?

 

Rattle is only on acceleration and happens all the time, cold and hot. I looked this evening and the latest programming was back in 2018. I tried to connect to Wi-Fi and get the latest software update but couldn’t get it to come through.

 

First try a tank of high octane fuel, even if it has crappy alcohol in it, try 91 or 93 if you can find it and see if the engine rattle goes away upon accelleration.

 

Is this a 4X4? Sounds like this?

 

I have the same issue with the rattleing noise. my rattle only occurs on decel and on cold starts. Also it gets better as temp increases and i have gotten the PCM reproggramed in the year and a half.