It does become a customs issue, although not an immigration issue. Customs of either country require you to drive vehicles that is plated with your country (state/province) of residence.

Being a PR does not make a resident of Canada if you do not live in Canada in the context of driving. In other words, if you live in US, drive a US plated vehicle and if you live in Canada, drive a Canadian plated vehicle, irrespective of your immigration status in either of the countries.

My wife has been denied entry to her car (not to her) for driving a US plated rental car while we lived in Canada. Meanwhile, I have been a PR and not lived in Canada and I have driven US plated vehicle into Canada with no problems.

Of course, there will be additional questioning if there are discrepancies and as long as you can answer them satisfactorily, no problems.

Apparently, according to the Windsor border officer, Detroit metro airport rents cars with ON plates, Don't know for sure, though.

Here is the interesting thing. Due to widespread inconsistencies in the border officer's ruling, you may be let into the country contrary to what I said above, but then there might be another time when the officer reads you the riot act and follows the actual policies. So exercise your best judgement.

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Dimple2001

You are right. This can become an issue, especially if we are speaking of extended absences as a PR from Canada. Ultimately, everything is at the customs/immigration officers discretion/pleasure.
It is best to avoid all these complications as far as possible, but like Dimple mentioned, you might get lucky and not have an issue but it is certainly no guarantee.

What about if PR is driving US plate number car (Personal car and usa insurance). Can one say that they are returning back to Canada after spending a year or so in USA with this car and other stuff as part of their goods to follow.
Though i am not sure about how much time is allowed to take their stuff through custom/border after initial landing.
Any choice of port/ entry from below in terms of ease
1) Queenston-Lewiston Bridge, Queenston, ON / Lewiston, NY
2) Ambassador Bridge Windsor, ON / Detroit, MI
3) Detroit and Canada Tunnel Windsor, ON / Detroit, MI
4) Blue Water Bridge, Sarnia, ON / Port Huron, MI

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Desibanda