Referencing both the owners and shop manual, say to replace the AT fluid every 45K miles, but absolutely nothing about the manual transmission. Did they forget this?
Was the same with my Honda's and Cavalier, with MT's, never touched it. O4 Cavalier was still good with 150K miles on it, but to the wrecking yard it went, unibody was a pile of rust.
But on all these cars, sure had to lubricate the linkage. Already stated that WD-40 is crap.
Only thing the shop manual says is 2.32 quarts (2.2 liters) is the capacity. and to use GM Part No. U.S. 19259104, in Canada 19259105 MT fluid, dealer should charge 0.5 hours to replace it providing they could hit that small hole. Ha, can't even hit that much larger hole when adding engine oil.
Over the years, never had MT seal leaks, but sure had my share with AT's and those torque converters can sure burn up the fluid in these things. Driving these things for years, my old 49 Olds, first one, would shift into neutral when sitting for a half a day waiting for a traffic light to change to green. This is when that fluid really gets red hot.
Also considered that very short tube like six inches long at that bottom of the radiator was a very bad joke, never was sure if this was a cooler or a heater. So would take the outlet of that tube and add an aftermarket real cooler in series with this line. But didn't have to do this with my 88 Supra, already has a good one.
I see the Cruze automatically switches to neutral, but with lack of a dipstick said the heck with this, got the manual. With even the slightest loss of AT fluid on these things, those clutches will burn up in a hurry, on most vehicles without any warning. Never learned if the Cruze gives this warning, don't care, won't have one.