A fuel injector stuck open. Had almighty shuddering so pulled off interstate and called for a tow. Unfortunately my tow package at the time only allowed a tow to nearest dealer ( so car was towed to lakeshore dealership in Slidell Louisiana .
Well before I called for a tow I looked under the hood and discovered all my coolant gone

checked around vehicle and saw no leaks so knew it was in the motor

Called the dealership and told them the situation ( I had to get a rental as I live in Florida) called them at least 5 times and advised them not to run the motor as it was full of coolant !! So what did they do? After changing the fuel injector at a price of 1500.00 they ran the motor for 5 mins until it blew
Unfortunately I live 200 miles away so they had me over a barrel and I was leaving the following week to go TDY for several months. So all I could do was pay them and pay for a tow to the house , when I got it home first thing I did was drain the oil and what do you know ....... All the coolant came out !!
Got the motor removed and opened up and one of the cylinder liners windowed destroying one piston and the valves
If I wasn't about to leave the area for months I would have been taking the dealership to court to fix the damage unfortunately timing and military duty prevented that so have had to suck up the costs for the rebuild!
Urgh I hate dealerships !!!
So I have been ordering parts piecemeal