BRAND NEW WINTERS CHAMPIONSHIP QUICK CHANGE REAR END WITH FLANGED AXLES (PART #604-3760; WINTERS PART #SR2525 AND SR2980-58"). THIS REAR END MEASURES 58" AXLE FLANGE TO AXLE FLANGE. MORE THAN TRADITION, WINTERS CHAMPIONSHIP QUICK CHANGE REAR END FEATURES THE SPRINT CAR CENTER WITH A 10", 4.12 RING & PINION, HEAT TREATED LOWER SHAFT, WINTERS TRACK DIFFERENTIAL (SEE BELOW), AXLE SEALS AND A SET OF 10 SPLINE, STRAIGHT CUT GEARS. INCLUDES STOCK APPEARING FLANGED 31 SPLINE AXLES THAT WILL ACCOMMODATE AFTER-MARKET DISC OR STOCK BRAKES. THESE REAR ENDS ARE A FANTASTIC ADDITION TO ALMOST ANY STREET ROD, HOT ROD, OR RESTORATION PROJECT FEATURES: WINTERS 10", 4.12 RING & PINION HEAT-TREATED LOWER SHAFT WINTERS TRACK DIFFERENTIAL, WHICH YOU CAN SEE PICTURED BELOW VIRTUALLY UNBREAKABLE, PARALLEL GEAR DESIGN AUTOMATICALLY SENSES WHEEL SPIN AND DELIVER POSITIVE TRACTION 31 SPLINE FLANGED AXLES WITH BEARINGS, BEARING RETAINERS, AND STUDS DRILLED FOR USE WITH 5 X 4.5" AND 5 X 4.75" BOLT PATTERNS AXLE SEALS 1310 SERIES FRONT PINION YOKE INCLUDES A SET OF WINTERS 10 SPLINE GEARS; THE DEFAULT GEAR SET IS #8501, WHICH HAS 21 SPLINE UPPER AND LOWER GEARS, YIELDING A 4.12 GEAR RATIO. IF YOU WOULD LIKE TO GET A DIFFERENT SET INSTEAD, JUST LET US KNOW WHEN ORDERING, AS WE HAVE THE COMPLETE LINE IN STOCK THE AXLE FLANGES ON THIS REAR END ARE THE BIG BEARING FORD (NEW STYLE), ALSO KNOWN AS "TORINO": WE HAVE DRUM BRAKE KITS AND WILWOOD DISC BRAKE KITS AVAILABLE TO BOLT DIRECTLY ON THIS REAR END. THIS REAR END COMES ASSEMBLED WITH THE TUBES INSTALLED SHIPS VIA UPS IN 2 SEPARATE BOXES BY REMOVING THE SIDE BELLS WITH THE TUBES INSTALLED TO SHIP IN ONE BOX AND SHIPPING THE COMPLETE CENTER SECTION IN ANOTHER BOX YOU CAN SEE MANY DIFFERENT DIAGRAMS TO THE RIGHT WITH ALL THE DIMENSIONS OF THIS REAR END