If you have access to his Google account, and he has mobile data and Location enabled on his phone, than yes you can remotely track his movements. So it's pretty conditional and without all three you're not going to be able to.
But it's important to distinguish what we see in movies with reality. Just tracking someone because you want to isn't a likely occurrence. Even ignoring the privacy aspect, there are technology limitations to just target someone and document all their actions. Even law enforcement doesn't have the resources to do that for the general population, perhaps for targeted individuals but not all of us at the same time and on-the-fly.
You could take the underground path and install some kind of stalker software on his phone to keep track of where he is, but that's crossing legal boundaries and if he discovers the situation he can then call the cops on you. And it's something you need to do beforehand, not after-the-fact, and you need physical access to his phone without his awareness of what you'll be doing. Some parents do use similar technology like parental control software to monitor their kids remotely, but that's a different situation where the parents have legal responsibilities over.their own offspring.
Instead of hiring a hacker, if you still don't want to involve law enforcement you might be better off hiring an independent private investigator to track down your car. And unless there's actually some valid reason as to why he hasn't returned it to you, this matter is a good reason for you to deny loaning your car to him in the future.
