The 9-inch rear end isn't as heavy , compared to the 8-inch, as most people think.

A drum brake 8-inch rear weighs 170 lbs. A comparable drum brake 9-inch rear end weighs 194 lbs. --only 24 lbs. difference. But in strength, the 9-inch is much more durable.

FORD REAR END WEIGHT COMPARISON 8"

8-inch Rear End Assembly Weight : 170 lbs.

1. Housing: 36 lbs.

2. Axles: Medium Journal, 28-spline -15 lbs. ea.

3. Brakes: Small 10" x 1¾" Drum Assemblies - 22 lbs. ea.

4. 3rd Member: Reinforced Revision 8-inch Case - 60 lbs.





9-inch Rear End Assembly Weight: 194 lbs.

1. Housing: 38 lbs.

2. Axles: Large Journal, 28-spline - 18 Lbs. ea.

3. Brakes: Massive 11-1/32 x 2½" Drum Assemblies - 26 lbs. ea.

4. 3rd Member: Conventional Diff. - 68 lbs.
a. w/Traction-Lok Diff. - 71 lbs.

(24 lbs. Difference Between Drum Brake 8" & Drum Brake 9" Rear End Assembly).




Versailles Disc Brake Rear End Assembly Weight: 215 lbs.

1. Housing: 39 lbs.

2. Caliper: w/Pads, Anchor Plate & Flexible Brake Hose - 24 lbs. ea.

3. Axles: 20 lbs. ea.

4. Rotors: 10 lbs. ea.

5. 3rd member: Conventional Diff. - 68 lbs.

(45 lbs. Difference Between Drum Brake 8" & Disc Brake 9" Versailles).




Wheel/Tire Comparison:

1. Stock '66 Mustang GT Styled Steel Wheel w/ P195/70R-14 Tire - 46 lbs. ea.

2. Weld Draglite Forged Aluminum Wheel (15" x 8") w/ P245/60-15 Tire - 38 lbs. ea.




Miscellaneous:

1. 8" Drum Brake Assembly: (10" x 1¾" Drums): 22 lbs. ea.

2. 9" Drum Brake Assembly (11-1/32" x 2½" Drums): 26 lbs. ea.

3. Lincoln Versailles Disc Brake Assembly: (10½" Rotors) 30 lbs. ea.

4. Lincoln Mk VII Rear Disc Brake Rotor/Caliper Assembly Weight: (11¼" Rotors) 22 lbs.ea.

5. Ford Explorer Rear Disc Brake Rotor/Caliper Assembly Weight: (11¼" Rotors) 25 lbs. ea.



http://www.ultrastang.com/Rearinfo.asp?Page_ID=1

 

Great info!

(and great to see you here Steve!)