I owned a 1995 chevy pickup and would restrict airflow in the winter to assist in warming up quicker to get heat from the blower. Do any owners block off their radiators in cold weather on the 2017 5.3 v-8 motor.?

 

I've seen it done, and alot with big rigs in high country. I'd suggest a 195 tstat if you don't already have one. Personally I'd not block the airflow to the radiator, but I also don't live in extreme cold climate.

 

On diesels it's a thing, primarily because they are so cold blooded due to massive cooling systems built for has hard as they work.

On gas motors, if it's not warming up you'd want to look at the thermostat and fans, determine if one or the other is causing it to over-cool, and repair. You can block some of the radiator off, but I personally haven't found the need to on anything built after 1990.