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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1986 🢒 Astro - 2WD 🢒 Bulletins 🢒 4L60 Automatic Transmission - New Sprag Assembly, Forward Clutch to Overrun Clutch Hub

4L60 Automatic Transmission - New Sprag Assembly, Forward Clutch to Overrun Clutch Hub

Subject:4L60 Automatic Transmission -- New Sprag Assembly, Forward Clutch to Overrun Clutch Hub

Models:1982-1986 Passenger Cars and Light Duty Trucks
with 4L60 Hydra-Matic Transmission (RPO MD8)



Object Number: 2087889 Size: MF
(1)The notches above each sprag must point up as shown when assembled into the outer race.
(637)Bearing Assembly, Input Sun Gear
(638)Snap Ring, Overrun Clutch Hub Retaining
(639)Hub, Overrun Clutch
(640)Wear Plate, Sprag Assembly
(641)Retainer and Race Assembly, Sprag
(642)Forward Sprag Assembly
(643)Retainer Rings, Sprag Assembly
(644)Outer Race, Forward Clutch
(660)Washer,Thrust (Input Carrier to Race)

The New Forward Clutch Assembly Changes are as Follows:
    • Two more Sprag Elements (28 total)
    • Larger Inner and Outer Race Diameters
    • Solid Steel End Retainer Rings

The new design sprag can be used on models 1982 through 1986, by replacing the entire assembly (637 -- 644). Individual components are NOT inter-changeable.

Important: The wear plate (640) and input thrust washer (660) are not required with the new sprag. Use of the thrust washer and wear plate with the new sprag assembly will cause a misbuild (correct end play cannot be obtained).