About 3 months ago I (44m) needed to borrow my stepfathers (74m) truck, a 2019 GMC Sierra. To tow a U-Haul trailer with my car on it to get it fixed. He was hesitant at first but my mom convinced him to let me use it for about 2 hours.

Now a little background, he didn’t raise me at all getting married to my mom when I was about 25. He also has this thing for his “things” especially his vehicles. He is always over maintaining them and washing them. and always worried about his trucks and cars more than people I think

One thing he very particular about is the gas he puts in his truck. He only puts BP 93 octane gas in his truck, but the owners manual states it only needs 87.

The thing is that I didn’t know this and I filled his truck up, you know as a nice gesture for letting me borrow the truck. I used my Sams club card and filled it up with 87.

The day after he calls and asks for a gas receipt (apparently he saves all gas receipts and has a log book of all the gas he ever bought for the truck). And I told him I didn’t get one as I didn’t think it was a big deal. But to him it was the end of the life of the truck. And he started his rants about how I don’t “value” things etc. and don’t take care my vehicles (which is a lie, I take care of my stuff very well, my daily is over 15 years old) because I don’t obsess over the things that don’t really matter on a car.

So now he wants me to pay for the flushing and replacing of the fuel system in his truck now (yes he paid the dealership $6,000 to replace his fuel tank, pumps and injectors). And also that he is going to “sell” the truck because of the “damage” I did by putting Walmart gas in his truck. And if I don’t pay him the $6,000 he is going to sue me.

Does he have a leg to stand on in court as this isn’t the first time he sued someone over petty things (sued his brother once over a tree and won). but not me.