Like others have said,check the belts- if worn-cracked-have small pieces missing-ect-have glazed sides or sit too deep in the pulley.
If 2 stage- check the shear pins or sometimes called shear bolts.
Good idea to pull the bolts and grease the augers so they spin. So when the errant rock or newspaper gets caught- the shear bolts do their job.
DON'T use hardened bolts. Your gear box will thank you.
Also might check the clearance between the impellers and side of the intake tube. Should be less than 1/8 inch.
Use an impeller kit, ie: pieces of stiff rubber belting bolted to the vanes of the impeller, just touching the sides.
Use liquid soap and allow it to wear in, tube might be out of round.
If you had a large enough gap this should decrease the gap and increase your throwing distance.
Check all bearings and keep tire air pressure the same,won't track straight.
Tighten nuts and bolts,grease shafts where gears ride and move.
Above all: KEEP FINGERS AND HANDS OUT OF THE CHUTE!!!!!!
Stay Alert Stay Alive !!!
T.J.