I just turned 313,000 on my 2009 Chevy Impala last week, mostly all highway miles but no major repairs to engine and nothing on transmission. Regular maintenance, few sensors, battery, tires brakes, just normal stuff. Body's perfect no rust.
Runs like a top, still average 30 mpg hwy and uses no oil yet. I drive it every day for work and put on from 1100-1700 miles weekly.
I do live in a northern climate so I do switch over to 4 wheel drive in the winter and have stored this Impala over the last several winters so maybe not driving in those cold times helps.

 

 

I have the 2009 Impala LT and it has 291,313 miles on it. It’s my daily driver, it hasn’t needed any repairs besides regular oil changes. It runs like a dream and literally not a single thing is wrong with it. It’s like a new car. It still has plenty of life left in it for sure. It was taken care of it’s whole life

 

2006 Impala original motor and tranny still going.

 

Posted earlier that I had 273K on our 2003 Impala 3.4. It's now 316K but did need a head gasket, LIM gasket and a little thing called a torque converter.