I have a 2015 F250 Diesel that has started to crank a little longer when the engine is hot. When the engine is cold it starts instantly. When the engine is hot is cranks a little longer, probably not long enough for most to notice but since I drive it every day it is noticeable to me. It always starts it just takes a second or two longer. I took it into the dealership to have them look at it (along with some other issues) but they claim it sounded normal. I’m not really certain that they really looked at it though. They kept on blaming the batteries even though the motor was turning over at a normal rate. They said that they couldn’t really diagnose things until they installed new batteries (sounds like bullshit to me). I changed the batteries myself and unsurprisingly it made no difference. My gut feeling is that there is low fuel pressure when the fuel is warm possibly due to a failing high pressure pump . My warranty is going to expire in a month so I’d like to get this fixed if it is a problem. Have any diesel techs out there seen something like this before? Thanks in advance for the help.