Why is this post modded interesting? It's wrong on so many levels...
First of all, it's the 14th Amendment that you'd be concerned with, not the 5th. The 5th Amendment relates to action undertaken by the federal government. The 14th amendment extends due process to the states.
Procedural due process relates to procedure - like a trial. This case seems to have been decided on the basis of whether or not a search took place, not the admissibility of the evidence. Procedural due process has no relevance. You can say that the decision was wrong, but as is - you're missing the mark.
"Substantive due process" doesn't mean much without some context. How exactly does this violate SDP? What is it about this that so fundamentally offends the concept of ordered liberty?
Most importantly, though, where the hell is your argument about "using his property for a public purpose" coming from? Got any sort of backing for that?
For one, cars have almost no privacy interest to begin with. Police can stop you while driving and search your car based on probable cause alone. (Chambers) Until only a few weeks ago, once arrested while driving, they could put you in the back of the squad car and then go and search the passenger compartment to ensure the officer's safety, (even though he's clearly already safe...) as a matter of routine. (Stunningly, the court made a sensible decision and reversed this in the Gant case.) They can also search your car for "inventory" purposes when it's impounded. (Opperman)
Virtually nothing having to do with cars requires a warrant.
The court held that "tracking" your car is the equivalent of visually tracking it. How does it matter that they're using your property to track YOU? Who else's car would they track? Beside, as Katz pretty well settled 40 years ago, the 4th amendment (the only one that's relevant to this question,) protects people, not places (or things!) It's all about what you should expect when you're driving in your car.
Really, this seems like its already a well-settled question. US v Knotts and US v Karo already established that the police can use "beepers" placed on a car to track them. This decision is just updating the decision slightly to keep up with the times. Based on Kyllo, the prevalence of GPS nowadays, and the complete disregard for privacy in cars, I can't believe this makes the news...