4L60/65/70E Heavy Duty Sun Shell - Genuine The Beast

4L60E 4L65E 700R4 The Beast Sun Gear Shell

Extreme duty upgrade for the 700R4 4L60E 4L65E transmission
Fits all units 1982-up

The original equipment sun gear shell is notoriously weak in the splined area.
Especially with 1996-on units, the originals are even less hardened!
Pre-'96, GM engines were TBI and idled at higher RPM after cold start and needed more hardness to survive stripping (at least through the factory warranty period).

The Patented "Beast" is incredibly strong in comparison.  The splined area is considerably thicker, and also reinforced by a large chamfered area to help resist twisting common with the thin stock type.
Please see comparison pic in the gallery!

US Patent No. 6,561,944