I think the placement in the garage is causing the issue.
I have three of them:
1. A small 30 year old Sanyo cube fridge that will turn water bottles into ice slabs if not adjusted carefully.
2. A large Danby (about 4.3 CU Ft) that we use for a beverage fridge in the kitchen. We keep the temp in the middle of the thermostat and everything is plenty cold.
3. A slightly smaller GE that we keep in the basement. I keep it about 5 or 6 and it does keep stuff cold (although, not as cold as the 2 above,) Prior to this, I had a Magic Chef the same size which this one replaced (it had an unfortunate defrosting accident.) These fridges are such commodities that the GE was exactly the same as the Magic Chef, except it was black and had a GE badge on it. It was used in an office setting until I retired. Kept everything cold, although I could never crank it down and get a true "Ice-Cold," like the other two.
You can probably keep it in the garage, although you are going to have to keep it cranked and expect it to cycle. You can probably expect a shorter life cycle, although these things are so cheap that it is not a huge deal.