I need to lift the back of my truck (2010 4WD). I’d be comfortable lifting the front with park engaged, because the drive to the rear is locked. In 4wd, will the front be similarly locked to prevent rolling when I lift the rear axle?

 

Yes, as long as BOTH front wheels are on the ground

Rangers use a 4WD transfer case so in 4WD both driveshaft are directly connected to transmission via chain drive

An AWD transfer case use a fluid coupler so no direct connection

An BOTH front wheels on the ground because front axle is OPEN type differential so if one wheel can spin/move it WILL

 

It’s better to chock the front wheels in some way. If you don’t have chocks (available at Walmart, harbor freight, autozone, etc) put a brick or log or something to physically prevent the wheels from rolling. Safety third after all.

 

Thanks to EddieQ and RonD for their input. Ron gave me confidence to move forward, but I made a trip to HF and bought chocks (really cheap) and used them in lieu of relying on the transfer case. Job now done (rear brake pad replacement).