Can the 2025 GMC Sierra 1500 make a U-turn?

No. Needs more than 40 ft.

41ft curb to curb

Street width, feet

Street 40 feet curb to curb.

2025 GMC Sierra 1500 Pro Regular Cab RWD. Top view, to scale.

2025 GMC Sierra 1500: turning circle by trim, 40 ft street
Trim	Circle, ft	Margin	One move
Pro	46.9	-6.9 ft	No
Pro Regular Cab RWD	41	-1 ft	No
2WD Reg Cab 140" Pro	44	-4 ft	No
Pro Double Cab RWD	46.3	-6.3 ft	No
Regular Cab Pro 4WD	41	-1 ft	No
4WD Reg Cab 140" Pro	44	-4 ft	No
Pro Crew Cab RWD	46.3	-6.3 ft	No
Double Cab Pro 4WD	46.3	-6.3 ft	No
Crew Cab Pro 4WD	46.3	-6.3 ft	No
Pro Crew Cab LB 4WD	49.5	-9.5 ft	No
SLE Double Cab RWD	46.3	-6.3 ft	No
Elevation Double Cab RWD	46.9	-6.9 ft	No
SLE Crew Cab RWD	46.3	-6.3 ft	No
Double Cab SLE 4WD	46.3	-6.3 ft	No
4WD Double Cab 147" Elevation w/3VL	46.9	-6.9 ft	No
Elevation Standard Double Cab 4WD	46.9	-6.9 ft	No
Elevation Crew Cab RWD	46.9	-6.9 ft	No
4WD Double Cab 147" Elevation w/3SB	46.9	-6.9 ft	No
Crew Cab SLE 4WD	46.3	-6.3 ft	No
SLE Crew Cab LB 4WD	49.5	-9.5 ft	No
4WD Crew Cab 147" Elevation w/3VL	46.9	-6.9 ft	No
Elevation Standard Crew Cab 4WD	46.9	-6.9 ft	No
SLT Crew Cab RWD	46.3	-6.3 ft	No
4WD Crew Cab 147" Elevation w/3SB	46.9	-6.9 ft	No
Elevation Crew Cab LB 4WD	50.2	-10.2 ft	No
Crew Cab SLT 4WD	46.3	-6.3 ft	No
SLT Crew Cab LB 4WD	49.5	-9.5 ft	No
Denali Crew Cab RWD	46.9	-6.9 ft	No
Crew Cab AT4 4WD	46.3	-6.3 ft	No
AT4 Crew Cab LB 4WD	50.7	-10.7 ft	No
Crew Cab Denali 4WD	46.9	-6.9 ft	No
Denali Crew Cab LB 4WD	50.2	-10.2 ft	No
AT4X Crew Cab 4WD	47.3	-7.3 ft	No
Crew Cab Denali Ultimate 4WD	46.9	-6.9 ft	No
Crew Cab Elevation 4WD	50.2	-10.2 ft	No
Double Cab Elevation 4WD	46.9	-6.9 ft	No

What this cannot tell you

Curb-to-curb turning circle as listed.

Mirrors and overhang need more room.