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Authorized Brand Dealer
Fulfillment From Multiple U.S. Warehouses
Enthusiast Owned & Supported
Easy Financing Available!
Authorized Brand Dealer
Fulfillment From Multiple U.S. Warehouses
Enthusiast Owned & Supported
Easy Financing Available!
Authorized Brand Dealer
Fulfillment From Multiple U.S. Warehouses
Enthusiast Owned & Supported
Easy Financing Available!
Authorized Brand Dealer
Fulfillment From Multiple U.S. Warehouses
Enthusiast Owned & Supported
Easy Financing Available!
Authorized Brand Dealer
Fulfillment From Multiple U.S. Warehouses
Enthusiast Owned & Supported
Easy Financing Available!
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Eaton
Eaton Detroit Truetrac 30 Spline Differential (1.29in Axle, 3.08-3.90 Ratio) for Select 1964-1972 GM 8.875in
This product will be available for sale in 2 weeks, but you can pre-order now to receive 10% discount!
The Eaton Detroit Truetrac is the premier maintenance-free, helical-gear limited-slip differential, designed to maximize traction and improve handling for select 1964-1972 Buick, Chevrolet, Oldsmobile, and Pontiac vehicles equipped with the 8.875-inch GM 12-bolt rear end.
Unlike traditional clutch-style differentials, the Truetrac utilizes a sophisticated gear-driven design that eliminates the need for friction modifiers or special additives. Under normal driving conditions, it operates as an open differential, but when wheel slip occurs, the helical gears automatically transfer torque to the high-traction wheel. This provides smooth, quiet engagement in both forward and reverse, making it an ideal choice for street performance, restoration projects, and light towing.
- Manufacturer Part Number: 913A555
- Axle Fitment: GM 8.875-inch (12-Bolt Passenger Car)
- Spline Count: 30 Spline
- Axle Shaft Diameter: 1.29 in
- Gear Ratio Compatibility: 3.08 - 3.90
- Design: Maintenance-free helical gear (clutchless)
- Performance: Optimized torque bias ratios for maximum acceleration
🔧 Fitment & Compatibility
| Year | Make | Model | Submodel |
|---|---|---|---|
| 1971-1972 | Buick | Centurion | Base |
| 1968-1972 | Buick | Electra | 225 |
| 1968-1972 | Buick | Electra | 225 Custom |
| 1964-1967 | Buick | Electra | Base |
| 1966-1967 | Buick | Electra | Custom |
| 1964,1970-1972 | Buick | Estate Wagon | Base |
| 1965-1967 | Buick | Gran Sport | Base |
| 1970-1972 | Buick | GS | Base |
| 1968-1969 | Buick | GS 350 | Base |
| 1968-1969 | Buick | GS 400 | Base |
| 1970-1972 | Buick | GS 455 | Base |
| 1970 | Buick | GS 455 | GSX |
| 1964-1972 | Buick | LeSabre | Base |
| 1965-1972 | Buick | LeSabre | Custom |
| 1964-1972 | Buick | Riviera | Base |
| 1965-1966,1971 | Buick | Riviera | Gran Sport |
| 1970,1972 | Buick | Skylark | 350 |
| 1964-1972 | Buick | Skylark | Base |
| 1968-1972 | Buick | Skylark | Custom |
| 1964-1969 | Buick | Special | Base |
| 1964-1967 | Buick | Special | Deluxe |
| 1964-1972 | Buick | Sportwagon | Base |
| 1966,1968-1969 | Buick | Sportwagon | Custom |
| 1964-1969 | Buick | Wildcat | Base |
| 1965-1970 | Buick | Wildcat | Custom |
| 1965 | Buick | Wildcat | Deluxe |
| 1966 | Buick | Wildcat | Gran Sport |
| 1964-1972 | Chevrolet | Bel Air | Base |
| 1964-1972 | Chevrolet | Biscayne | Base |
| 1969-1972 | Chevrolet | Brookwood | Base |
| 1967-1972 | Chevrolet | Camaro | Base |
| 1967-1972 | Chevrolet | Camaro | RS |
| 1967-1972 | Chevrolet | Camaro | SS |
| 1967-1972 | Chevrolet | Camaro | Z28 |
| 1966-1972 | Chevrolet | Caprice | Base |
| 1964-1968 | Chevrolet | Chevelle | 300 |
| 1965-1969 | Chevrolet | Chevelle | 300 Deluxe |
| 1970-1972 | Chevrolet | Chevelle | Base |
| 1967-1972 | Chevrolet | Chevelle | Concours |
| 1969-1972 | Chevrolet | Chevelle | Concours Estate |
| 1969-1972 | Chevrolet | Chevelle | Greenbrier |
| 1964-1972 | Chevrolet | Chevelle | Malibu |
| 1964-1965 | Chevrolet | Chevelle | Malibu Super Sport |
| 1968-1972 | Chevrolet | Chevelle | Nomad |
| 1968 | Chevrolet | Chevelle | Nomad Custom |
| 1971-1972 | Chevrolet | Chevelle | SS |
| 1967-1970 | Chevrolet | Chevelle | SS 396 |
| 1966 | Chevrolet | Chevelle | Super Sport 396 |
| 1964-1967 | Chevrolet | Chevy II | Base |
| 1964-1968 | Chevrolet | Chevy II | Nova |
| 1964-1967 | Chevrolet | Chevy II | Nova SS |
| 1968-1969 | Chevrolet | Corvair | 500 |
| 1964-1967 | Chevrolet | Corvair | Base |
| 1965-1966 | Chevrolet | Corvair | Corsa |
| 1964 | Chevrolet | Corvair | Deluxe |
| 1964-1969 | Chevrolet | Corvair | Monza |
| 1964 | Chevrolet | Corvair | Monza Spyder |
| 1964-1972 | Chevrolet | Corvette | Base |
| 1965-1972 | Chevrolet | El Camino | Base |
| 1968-1972 | Chevrolet | El Camino | Custom |
| 1968-1972 | Chevrolet | El Camino | SS |
| 1969-1970 | Chevrolet | Estate | Base |
| 1964-1972 | Chevrolet | Impala | Base |
| 1964-1967 | Chevrolet | Impala | SS |
| 1969-1972 | Chevrolet | Kingswood | Base |
| 1969-1972 | Chevrolet | Kingswood | Estate |
| 1970-1972 | Chevrolet | Monte Carlo | Base |
| 1969-1972 | Chevrolet | Nova | Base |
| 1969-1972 | Chevrolet | Townsman | Base |
| 1971-1972 | Chevrolet | Vega | Base |
| 1971-1972 | Chevrolet | Vega | Panel |
| 1964-1971 | Oldsmobile | 442 | Base |
| 1964-1972 | Oldsmobile | 98 | Base |
| 1964 | Oldsmobile | 98 | Custom |
| 1964-1967 | Oldsmobile | 98 | Holiday |
| 1971-1972 | Oldsmobile | Custom Cruiser | Base |
| 1964-1972 | Oldsmobile | Cutlass | Base |
| 1972 | Oldsmobile | Cutlass | Cruiser |
| 1964-1967 | Oldsmobile | Cutlass | Holiday |
| 1968,1971-1972 | Oldsmobile | Cutlass | S |
| 1967 | Oldsmobile | Cutlass | Turnpike Cruiser |
| 1967-1972 | Oldsmobile | Cutlass Supreme | Base |
| 1967-1968 | Oldsmobile | Delmont 88 | Base |
| 1967 | Oldsmobile | Delmont 88 | Holiday |
| 1965-1972 | Oldsmobile | Delta 88 | Base |
| 1967-1971 | Oldsmobile | Delta 88 | Custom |
| 1965-1967 | Oldsmobile | Delta 88 | Holiday |
| 1969-1972 | Oldsmobile | Delta 88 | Royale |
| 1964-1966 | Oldsmobile | Dynamic 88 | Base |
| 1964-1966 | Oldsmobile | Dynamic 88 | Holiday |
| 1964-1972 | Oldsmobile | F85 | Base |
| 1964-1966 | Oldsmobile | F85 | Deluxe |
| 1966 | Oldsmobile | F85 | Holiday |
| 1964 | Oldsmobile | Fiesta | Base |
| 1964-1966 | Oldsmobile | Jetstar 88 | Base |
| 1964-1966 | Oldsmobile | Jetstar 88 | Holiday |
| 1964-1965 | Oldsmobile | Jetstar I | Base |
| 1964-1966 | Oldsmobile | Starfire | Base |
| 1964 | Oldsmobile | Super 88 | Base |
| 1964 | Oldsmobile | Super 88 | Holiday |
| 1966-1972 | Oldsmobile | Toronado | Base |
| 1971-1972 | Oldsmobile | Toronado | Brougham |
| 1968-1970 | Oldsmobile | Toronado | Custom |
| 1966-1967 | Oldsmobile | Toronado | Deluxe |
| 1964-1972 | Oldsmobile | Vista Cruiser | Base |
| 1964-1967 | Oldsmobile | Vista Cruiser | Custom |
| 1964-1972 | Pontiac | Bonneville | Base |
| 1964-1970 | Pontiac | Bonneville | Safari |
| 1964-1967 | Pontiac | Catalina | 2+2 |
| 1964-1972 | Pontiac | Catalina | Base |
| 1971-1972 | Pontiac | Catalina | Brougham |
| 1964-1972 | Pontiac | Catalina | Safari |
| 1964-1970 | Pontiac | Catalina | Ventura |
| 1967-1970 | Pontiac | Executive | Base |
| 1967-1970 | Pontiac | Executive | Safari |
| 1968-1969 | Pontiac | Firebird | 350 |
| 1969 | Pontiac | Firebird | 350 HO |
| 1967-1969 | Pontiac | Firebird | 400 |
| 1967-1972 | Pontiac | Firebird | Base |
| 1970-1972 | Pontiac | Firebird | Esprit |
| 1970-1972 | Pontiac | Firebird | Formula |
| 1967 | Pontiac | Firebird | HO |
| 1967-1969 | Pontiac | Firebird | Sprint |
| 1969-1972 | Pontiac | Firebird | Trans Am |
| 1964-1972 | Pontiac | Grand Prix | Base |
| 1971-1972 | Pontiac | Grand Safari | Base |
| 1971-1972 | Pontiac | Grandville | Base |
| 1964-1972 | Pontiac | GTO | Base |
| 1970-1971 | Pontiac | GTO | The Judge |
| 1964-1972 | Pontiac | LeMans | Base |
| 1972 | Pontiac | LeMans | Luxury |
| 1969-1970 | Pontiac | LeMans | Safari |
| 1970-1972 | Pontiac | LeMans | Sport |
| 1971 | Pontiac | LeMans | T37 |
| 1964-1966 | Pontiac | Star Chief | Base |
| 1966 | Pontiac | Star Chief | Executive |
| 1964-1970 | Pontiac | Tempest | Base |
| 1964-1969 | Pontiac | Tempest | Custom |
| 1970 | Pontiac | Tempest | GT |
| 1964-1969 | Pontiac | Tempest | Safari |
| 1971-1972 | Pontiac | Ventura | Base |
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1340 Cobb Dr, Unit 1, Eustis, FL 32736
352-234-4458
Mon – Fri: 8:30 am – 4:30 pm
Sat: 9:00 am – 2:00 pm
Sun: Closed
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Eaton Detroit Truetrac 30 Spline Differential (1.29in Axle, 3.08-3.90 Ratio) for Select 1964-1972 GM 8.875in
This product will be available soon, but you can pre-order now to get on the list before others!
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The Eaton Detroit Truetrac is the premier maintenance-free, helical-gear limited-slip differential, designed to maximize traction and improve handling for select 1964-1972 Buick, Chevrolet, Oldsmobile, and Pontiac vehicles equipped with the 8.875-inch GM 12-bolt rear end.
Unlike traditional clutch-style differentials, the Truetrac utilizes a sophisticated gear-driven design that eliminates the need for friction modifiers or special additives. Under normal driving conditions, it operates as an open differential, but when wheel slip occurs, the helical gears automatically transfer torque to the high-traction wheel. This provides smooth, quiet engagement in both forward and reverse, making it an ideal choice for street performance, restoration projects, and light towing.
- Manufacturer Part Number: 913A555
- Axle Fitment: GM 8.875-inch (12-Bolt Passenger Car)
- Spline Count: 30 Spline
- Axle Shaft Diameter: 1.29 in
- Gear Ratio Compatibility: 3.08 - 3.90
- Design: Maintenance-free helical gear (clutchless)
- Performance: Optimized torque bias ratios for maximum acceleration
🔧 Fitment & Compatibility
| Year | Make | Model | Submodel |
|---|---|---|---|
| 1971-1972 | Buick | Centurion | Base |
| 1968-1972 | Buick | Electra | 225 |
| 1968-1972 | Buick | Electra | 225 Custom |
| 1964-1967 | Buick | Electra | Base |
| 1966-1967 | Buick | Electra | Custom |
| 1964,1970-1972 | Buick | Estate Wagon | Base |
| 1965-1967 | Buick | Gran Sport | Base |
| 1970-1972 | Buick | GS | Base |
| 1968-1969 | Buick | GS 350 | Base |
| 1968-1969 | Buick | GS 400 | Base |
| 1970-1972 | Buick | GS 455 | Base |
| 1970 | Buick | GS 455 | GSX |
| 1964-1972 | Buick | LeSabre | Base |
| 1965-1972 | Buick | LeSabre | Custom |
| 1964-1972 | Buick | Riviera | Base |
| 1965-1966,1971 | Buick | Riviera | Gran Sport |
| 1970,1972 | Buick | Skylark | 350 |
| 1964-1972 | Buick | Skylark | Base |
| 1968-1972 | Buick | Skylark | Custom |
| 1964-1969 | Buick | Special | Base |
| 1964-1967 | Buick | Special | Deluxe |
| 1964-1972 | Buick | Sportwagon | Base |
| 1966,1968-1969 | Buick | Sportwagon | Custom |
| 1964-1969 | Buick | Wildcat | Base |
| 1965-1970 | Buick | Wildcat | Custom |
| 1965 | Buick | Wildcat | Deluxe |
| 1966 | Buick | Wildcat | Gran Sport |
| 1964-1972 | Chevrolet | Bel Air | Base |
| 1964-1972 | Chevrolet | Biscayne | Base |
| 1969-1972 | Chevrolet | Brookwood | Base |
| 1967-1972 | Chevrolet | Camaro | Base |
| 1967-1972 | Chevrolet | Camaro | RS |
| 1967-1972 | Chevrolet | Camaro | SS |
| 1967-1972 | Chevrolet | Camaro | Z28 |
| 1966-1972 | Chevrolet | Caprice | Base |
| 1964-1968 | Chevrolet | Chevelle | 300 |
| 1965-1969 | Chevrolet | Chevelle | 300 Deluxe |
| 1970-1972 | Chevrolet | Chevelle | Base |
| 1967-1972 | Chevrolet | Chevelle | Concours |
| 1969-1972 | Chevrolet | Chevelle | Concours Estate |
| 1969-1972 | Chevrolet | Chevelle | Greenbrier |
| 1964-1972 | Chevrolet | Chevelle | Malibu |
| 1964-1965 | Chevrolet | Chevelle | Malibu Super Sport |
| 1968-1972 | Chevrolet | Chevelle | Nomad |
| 1968 | Chevrolet | Chevelle | Nomad Custom |
| 1971-1972 | Chevrolet | Chevelle | SS |
| 1967-1970 | Chevrolet | Chevelle | SS 396 |
| 1966 | Chevrolet | Chevelle | Super Sport 396 |
| 1964-1967 | Chevrolet | Chevy II | Base |
| 1964-1968 | Chevrolet | Chevy II | Nova |
| 1964-1967 | Chevrolet | Chevy II | Nova SS |
| 1968-1969 | Chevrolet | Corvair | 500 |
| 1964-1967 | Chevrolet | Corvair | Base |
| 1965-1966 | Chevrolet | Corvair | Corsa |
| 1964 | Chevrolet | Corvair | Deluxe |
| 1964-1969 | Chevrolet | Corvair | Monza |
| 1964 | Chevrolet | Corvair | Monza Spyder |
| 1964-1972 | Chevrolet | Corvette | Base |
| 1965-1972 | Chevrolet | El Camino | Base |
| 1968-1972 | Chevrolet | El Camino | Custom |
| 1968-1972 | Chevrolet | El Camino | SS |
| 1969-1970 | Chevrolet | Estate | Base |
| 1964-1972 | Chevrolet | Impala | Base |
| 1964-1967 | Chevrolet | Impala | SS |
| 1969-1972 | Chevrolet | Kingswood | Base |
| 1969-1972 | Chevrolet | Kingswood | Estate |
| 1970-1972 | Chevrolet | Monte Carlo | Base |
| 1969-1972 | Chevrolet | Nova | Base |
| 1969-1972 | Chevrolet | Townsman | Base |
| 1971-1972 | Chevrolet | Vega | Base |
| 1971-1972 | Chevrolet | Vega | Panel |
| 1964-1971 | Oldsmobile | 442 | Base |
| 1964-1972 | Oldsmobile | 98 | Base |
| 1964 | Oldsmobile | 98 | Custom |
| 1964-1967 | Oldsmobile | 98 | Holiday |
| 1971-1972 | Oldsmobile | Custom Cruiser | Base |
| 1964-1972 | Oldsmobile | Cutlass | Base |
| 1972 | Oldsmobile | Cutlass | Cruiser |
| 1964-1967 | Oldsmobile | Cutlass | Holiday |
| 1968,1971-1972 | Oldsmobile | Cutlass | S |
| 1967 | Oldsmobile | Cutlass | Turnpike Cruiser |
| 1967-1972 | Oldsmobile | Cutlass Supreme | Base |
| 1967-1968 | Oldsmobile | Delmont 88 | Base |
| 1967 | Oldsmobile | Delmont 88 | Holiday |
| 1965-1972 | Oldsmobile | Delta 88 | Base |
| 1967-1971 | Oldsmobile | Delta 88 | Custom |
| 1965-1967 | Oldsmobile | Delta 88 | Holiday |
| 1969-1972 | Oldsmobile | Delta 88 | Royale |
| 1964-1966 | Oldsmobile | Dynamic 88 | Base |
| 1964-1966 | Oldsmobile | Dynamic 88 | Holiday |
| 1964-1972 | Oldsmobile | F85 | Base |
| 1964-1966 | Oldsmobile | F85 | Deluxe |
| 1966 | Oldsmobile | F85 | Holiday |
| 1964 | Oldsmobile | Fiesta | Base |
| 1964-1966 | Oldsmobile | Jetstar 88 | Base |
| 1964-1966 | Oldsmobile | Jetstar 88 | Holiday |
| 1964-1965 | Oldsmobile | Jetstar I | Base |
| 1964-1966 | Oldsmobile | Starfire | Base |
| 1964 | Oldsmobile | Super 88 | Base |
| 1964 | Oldsmobile | Super 88 | Holiday |
| 1966-1972 | Oldsmobile | Toronado | Base |
| 1971-1972 | Oldsmobile | Toronado | Brougham |
| 1968-1970 | Oldsmobile | Toronado | Custom |
| 1966-1967 | Oldsmobile | Toronado | Deluxe |
| 1964-1972 | Oldsmobile | Vista Cruiser | Base |
| 1964-1967 | Oldsmobile | Vista Cruiser | Custom |
| 1964-1972 | Pontiac | Bonneville | Base |
| 1964-1970 | Pontiac | Bonneville | Safari |
| 1964-1967 | Pontiac | Catalina | 2+2 |
| 1964-1972 | Pontiac | Catalina | Base |
| 1971-1972 | Pontiac | Catalina | Brougham |
| 1964-1972 | Pontiac | Catalina | Safari |
| 1964-1970 | Pontiac | Catalina | Ventura |
| 1967-1970 | Pontiac | Executive | Base |
| 1967-1970 | Pontiac | Executive | Safari |
| 1968-1969 | Pontiac | Firebird | 350 |
| 1969 | Pontiac | Firebird | 350 HO |
| 1967-1969 | Pontiac | Firebird | 400 |
| 1967-1972 | Pontiac | Firebird | Base |
| 1970-1972 | Pontiac | Firebird | Esprit |
| 1970-1972 | Pontiac | Firebird | Formula |
| 1967 | Pontiac | Firebird | HO |
| 1967-1969 | Pontiac | Firebird | Sprint |
| 1969-1972 | Pontiac | Firebird | Trans Am |
| 1964-1972 | Pontiac | Grand Prix | Base |
| 1971-1972 | Pontiac | Grand Safari | Base |
| 1971-1972 | Pontiac | Grandville | Base |
| 1964-1972 | Pontiac | GTO | Base |
| 1970-1971 | Pontiac | GTO | The Judge |
| 1964-1972 | Pontiac | LeMans | Base |
| 1972 | Pontiac | LeMans | Luxury |
| 1969-1970 | Pontiac | LeMans | Safari |
| 1970-1972 | Pontiac | LeMans | Sport |
| 1971 | Pontiac | LeMans | T37 |
| 1964-1966 | Pontiac | Star Chief | Base |
| 1966 | Pontiac | Star Chief | Executive |
| 1964-1970 | Pontiac | Tempest | Base |
| 1964-1969 | Pontiac | Tempest | Custom |
| 1970 | Pontiac | Tempest | GT |
| 1964-1969 | Pontiac | Tempest | Safari |
| 1971-1972 | Pontiac | Ventura | Base |
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