Why is the 4L60e considered a POS
First of all, the 4L60e suffers from having undersized three / four, clutch discs, for the truck application.
There are two ways to improve the performance of those clutch discs. Increase the number of them, or increase the trans pressure, or both. When they add disc’s they have to be thinner to occupy the same space, so they tend to heat up faster being thinner.
The “e” in 4L60e, stands for “electronic”. The ECM controls the trans pressure using Throttle position, Mass Air Flow, RPM’s and Vehicle speed. There are other considerations also, but those are the main ingredients.
If your going through transmissions in a few thousand miles, I would expect there is something wrong with the ECM settings. Hooking up a pressure gauge and going for a test drive should quickly prove if all is proper.
In a manual transmission application, when the clutch pedal is released, spring pressure clamps the disc and pressure plate together. In the 4L60e, it is hydraulic pressure, provided by a pump that holds the clutch disc together. How tight they are depends on the settings in the ECM and it’s interpretation of the above mentioned input sensors.
The “Force Motor” tables in the ECM are where the settings are made on what trans pressure is used for the TPS and MAF input.
When power settings are high, the pressure is high and when power demand is lowered, the pressure drops to make the shifts smoother. Depending on the trans and how it is built, pressures can range from 60 psi to 300 psi.
I use separate controllers for my 4L60e and 4L80e. To me it is cheap insurance that the trans is operated properly for performance applications.
As far as the trans being a POS, the 4L60e itself is not the culprit in most cases. There are millions of them out there that work just fine, when they are used in a cars they were designed for. General Motors should have used 4L80e’s in all ½ ton trucks and up to start with IMHO.
Also, the newer vehicles have the torque control that drops the torque during shifts to try to improve the life of the tranny’s.
