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| | | Forums66 Topics128,151 Posts1,057,009 Members48,460 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: May 2001 Posts: 1,907 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,907 | I swapped my original 4.57 rear end for a 4.10. Would the 4.57 be called an Eaton HO or something like that?
1948 3/4-Ton 5-Window Flatbed Chevrolet 34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
| | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 |
Bill Burmeister | | | | | Joined: May 2001 Posts: 1,907 'Bolter | | 'Bolter Joined: May 2001 Posts: 1,907 | Longbox, Thanks! What would an Eaton HO72 be?
1948 3/4-Ton 5-Window Flatbed Chevrolet 34 Years. Now with a '61 261, 848 head, Rochester Monojet carb, SM420 4-speed, 4.10 rear, dual reservoir MC, Bendix up front, 235/85R16 tires, 12-volt w/alternator, electric wipers and a modern radio in the glove box.
| | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | it's essentially the same rearend, but with larger brakes, and perhaps heavier bearings at the wheel ends, which allows for a higher load capacity (7200 pounds vs 5200 pounds). The third members are interchangeable. The HO72 commonly found with the 5.13 gears, but some were 4.56. The HO52 is generally the other way around, with 4.56 being the common one. Both were also available in a 4.10 in some years.
Bill Burmeister | | | | | Joined: Jun 2009 Posts: 79 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2009 Posts: 79 | The main difference between the 72 and 52 axles was the 7200lb third member had a load bolt to prevent ring gear deflection with heavier loads as well as double taper roller bearings on the pinion shaft. The 5200lb third members don't have the load bolt and used a double ball roller bearing. The actual axles and wheel bearings were the same between the two. As far as interchangeability the two can be swapped with each other as well as the pinion, carrier and ring gear. The H052 was a 3/4 ton axle while the H072 was used by both 3/4 and 1 ton trucks, suburbans, and delivery vans. | | |
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