By far one of the most common transmissions in domestic GM trucks and SUVs the 4L60e is not without its own select set of common failures, design weaknesses, and aftermarket solutions.
On this 2001 1500 Silverado, one of the planetary assemblies decided to come apart at the center splined hub. Also, we often see reaction sun shells that crack and shear at the hub. Thats why we install “The Beast”, an aftermarket solution to this original design weakness. The Beast, is substantially thicker in the hub area and is pre-tempered for additional strength. I have yet to see or hear of one of these upgraded sun shells failing.
Another trouble code fix for these transmissions is the Trans-Go valve body spacer plate upgrade. Not only do we incorporate one of these into every 4L60e build that we do, but we are always impressed at the improved shift quality, and performance brought from the engineered improvements into the various flow passages in this plate. Just about every 4L60e we see has a valve body spacer plate with check ball ports mannered, dished and sometimes blown through. About one third have broken accumulator springs.