2017 Expolorer 2.3L Ecoboost, strange rattle at 50mph while engine low rpm.

[ZXMustang]

So this rattle happens when you have the cruise set or are trying to maintain 49-50 mph when the truck is in its OD gear.  When you just barely squeeze the gas to keep speed up a hill or just from starting to decel, the truck does not down shift but luggs a tad and starts to make this audible rattle.  You cant feel it but you can hear it.  Almost sounds like a heat shield rattling at this low RPM.  But if you give a little more gas, it shifts up a gear and the rattle goes away.  Its literally only reproducable between 49-50mph.  But its there and you can hear it on and off when the cruise is set and the truck is trying to maintain that speed.  Truck has 500 miles on it, bought it brand new.  I dont want to waste the dealers or my time bringing it in if this is normal because its lugging or pinging.  I just filled it up with 93 octane and will use that for the time being to see if it helps.  But most likely Im thinking this is a mechanical rattle of something loose.  Please help if you can.

2017 2.3L Ecoboost Explorer XLT.  This is my wifes first new car in like 6 years, and this is really depressing.

[SHOdded]

Welcome to EBPF!  Sorry to hear of troubles already with the '17 ...  Most times, a rattle on EB engines is heard at startup, where it lasts a brief second or two.  If the rattle is extended, it is almost certainly due to the timing chain(s).  Inadequate oil pressure/timing chain stretch are believed to be the culprits.  Transmission programming tends to not be so good from the factory, and aftermarket tunes take care of that.

If you want to DIY, you can take the appearance cover off and poke around a bit to see if anything is loose.  I would limit it to that, the vehicle being so new.  If nothing jumps out at that point, take it in to the dealer, make sure a tech rides with you and demonstrate what is going on.  It could be a blowoff valve, it could be a turbo at spindown, let them figure it out.

[glock-coma]

Do you have any way of logging obd2 engine info?
Mx Bluetooth adapter would work.
That would narrow down what to look for if its actual knock or just mechanical rattles from the exhaust.