Well guys, I have a fun one!

I have a reasonably stock 2017 F150 XL 4x4 3.5 Ecoboost, 54k miles.

Sat- Factory battery dies without warming. Got a new battery, did the BMS reset, drove for a min. Turned it off, tried to turn it back on and I i got power but no crank. Like the starter didn't get any voltage. After an hr of lightly tinkering, no luck. Later that night fired right up.

Sun - Fired right up drove fine no issues

Mon - Fired up, drove it to work, no prob. Mon evening when leaving it wouldn't start again. Tried jumping and charging no luck. Same thing, starter wasn't getting juice to crank but you can tell all pumps and everything we're coming on. Battery was sitting about 11.8V charged up to close to 13V and still no crank

Tues (today)- am, fired right up, when I drove it though it was stuck in 7th! Wouldn't shift. Put it in park and reverse and it started shifting normal. When driving it home it would skip gears and go 1-3-5-6-7-8 and not only skip but shift early, like I was 8th but going like 40 and it wouldn't downshift accordingly. I had to basically come to a complete stop for it to downshift. In manual mode, it would shift into each gear but was slow at 2 and 4, the gears it was skipping on.

There are no codes on the dash btw! OBD reads clean (naturally in these situations).

Only oddities before this are about two weeks ago I started to see a very slight delay when cranking at the start. And I mean like maybe a half second. It's just more than I'm used to. Last oddity is my dashboard will occasionally go back to the home screen instead of stay on my current trip screen. It doesn't reset, just goes to the main selection screen.

I've checked all fuzes, most relays and the grounds under the hood and behind the cabin fuze box and everything checks out.

Anyone have a similar experience or ideas?

Thanks guys!
-Matt

 

Welcome, tell us more about the truck!

 

My gosh, I suck! I updated the post but it's a 2017 F150 XL 4x4 3.5 Ecoboost, 54k miles.

 

Starter.

 

Totally agree! Had almost the same thing happening with my 2017. I have ESP with Ford and it got flat bedded from my driveway to the dealer. New starter installed and everything has been good ever since. I thought it was a fairly expensive repair for just a starter but it only cost me 100 bucks for my deductible.

 

I guess my question is then, if it were the starter, how would that impact my transmission acting the way it does? I can easily believe it is that starter! Given the delay at the crank, but the other electrical things with the dash may just be something else.

 

Grounds. Check and clean all your grounds. Can't stress this enough with these trucks. There's like 15 locations.
dont just look at them. Remove bolt and wire wheel contact points and put dielectric grease on make sure all it tight.

Goodluck

 

Awesome! Will do!

 

6 or 7 under hood and radiator support, ground on starter and cross members.
passenger side on frame to body under passenger door is a common one that breaks and all the way back to rear bumper you'll find Grounds. I used a wire wheel on a drill to clean contacts on ground wire and body. Cleared up my issues with my 17
and acouple under dash lol

 

You guys were correct! It was the starter! I haven't seen any bugs with the transmission since I've replaced it too.

Thanks again everyone!
-Matt