You can drywall in a garage without insulation. Drywall does not need insulation. However, your garage will be better off insulated. Drywall is not an alternative to garage insulation.
Insulation plays a critical role in retaining heat and cold; it should keep your garage comfortable. Without insulation, the wall performs only a cosmetic function (at least for the most part). However, if you do not have insulation in the garage attic, you are wasting your time insulating the walls. The heat goes through the lid long before the walls help.
Let's see why this is important, why drywall in a detached garage, what to do when the drywall is lifted, use plywood, start with an unfinished garage, maintenance and when to call a professional. Garage doors are large and work like a fourth wall, so insulating the walls and roof of the garage to standards recommended by energy conservation agencies won't make any difference unless you also have an insulated garage door. Garage fires tend to take longer to detect, so they tend to be larger, more widespread, and cause more damage than other household fires. However, if your car is never in your garage because it's a full gym, workshop, and band rehearsal space, then isolation makes sense.
Drywall can provide a lightweight canvas that not only reflects light better, but can also be primed and painted for further customization. If you insulate your garage and want it to look good because you use it more often, you have the extra cost of drywall to finish it. My current home has textured drywall torn down on the walls and ceiling and, so far, of all my previous homes, it's my favorite. Insulating your garage provides a sound barrier that prevents sound from entering and leaving your home.
So if you don't need to insulate and heat your garage, why bother? People like to use the word “comfort”. Hanging drywall in your garage is a great way to improve the room and make it look more like an extension of your home. I have addressed the considerations of drywall compared to OSB before for finishing a garage and am currently installing boat siding in my own garage. Keeping the rollers, guides and door springs lubricated, the garage door balanced, and the sensitivity of the door tight are great ways to make the most of the number of years of the garage door and openers.
We've outlined the pros and cons of garage insulation so you can decide if it makes sense for your home.