Sonnax 4L60 Heavy Duty Reaction Shaft Kit

Sonnax 4L60 Heavy Duty Reaction Shaft Kit

Transtar Industries & Sonnax

Transtar's community of suppliers represents the most trusted and experienced in the industry. Sonnax shares our vision and meets the premium standards we set for all of our product offerings. We rely on the best aftermarket and OE suppliers in the industry. 

For GM Applications: 4L60, 4L60-E, 4L65-E, 4L70-E:

Part Number: S74602BHPK


GM 4L60E series reaction shafts used in high-torque applications — and especially in heavy vehicles — suffer from two common issues that require replacement: The splines that engage the rear planet can twist and the splines that engage the ring gear fret/wear. OE and other aftermarket versions are made from lower strength, plain carbon steel. Sonnax heavy duty reaction shaft 74602-01K is made from high-strength chromoly steel alloy to eliminate spline twist and spline wear.

The shaft kit includes a shim and two bearings. One bearing is for the shaft-to-reaction shell, the other bearing plus shim combination is for shaft-to-front carrier and makes it a universal it for all input carrier styles. This includes all four- and  ive-pinion carriers found in early 700-R4, 4L60-E and 4L65-E units including the Sonnax 2.84 ratio six pinion input carrier kit as well as late-style four- and five-pinion 4L60-E and 4L70-E carriers with lip-style bearings. 
  • Prevents spline twist and wear
  • High-strength alloy outperforms all other OE and aftermarket shaft material
  • Universal  fit
Kit Contents
  • Reaction Shaft With Bushings
  • Bearing Reaction Shaft-to-Shell
  • Bearing Reaction Shaft-to-Front Carrier
  • Shim



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    This change will primarily impact parts such as end plugs, valve kits and bushings that come in small bags. In general, instructions will continue to ship with larger components and boxed products such as Zip KitsĀ® and The Sure CureĀ® kits.

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