Fixed that loose negative battery cable on my gas Cruze on day two, could wiggle it with my fingers. Use a file to get a gap in there so it could be tightened. But then after a couple of years, was getting a two volt drop between the negative battery terminal and the ground point.
They crimped that negative battery cable onto bare copper wire that corroded on the inside. Just run your engine, kick on the blower motor, and put a voltmeter between the negative battery terminal itself and where its grounded. Should be more like zero volts and certainly not two volts.
I had to solder that wire into the terminal, now its good. If you get a new battery cable made the same way, will also have problems with it in a couple of years or so, Dipping that bare copper wire in a solder pot would be a permanent cure for this problem before crimping it.
Also had problems with my ignition relay, responsible for giving a sharp voltage to reset the computer circuits, had to reboot the system several times that required opening the driver's door. Diesel should be the same, replaced that POS made in China relay with a good Panasonic relay. But had to modify the contacts first so it would fit.
Guys don't recall when the USA made the best relays in the world. More history.
Battery in my Cruze only lasted 33 months, developed a high self discharge rate, would charge properly, but would be dead 30 hours later. First two fancy Chevy dealers refused to replace it, but one in a 75 year old shop replaced it instantly. But still only came with the remaining three months warranty. If you want a good warranty, have to lay out a couple hundred bucks for it.