New GM SK 4L60E 4L65E 4L70E Transgo Shift Kit Code 1870 P1870 1993-2010. SK4L60E. Fits General Motors 4L60E, 4L65E and 4L70E 1993-2010 "Except Hybrid units". Includes our exclusive "ISO-CONV Valve" a one piece valve that replaces both the OEM Isolator and Converter Regulator valves. This transmission has been utilized in many different vehicles and our kit contains parts and items necessary for an extensive recalibration of this unit regardless of vehicle size, power, engine or axle combinations. Upgraded "ISO-CONV Valve train" with new spacer added for vehicles with Cylinder Deactivation. Addresses and Fixes trouble Code 1870. Trouble light & Hard 1-2 shift. No lockup and/or 4th. Corrects damaging harmonic extreme bounce in pressure gauge readings on PWM (Pulse Width Modulated) pump that causes pump failure and/or premature wear on valves and pump assembly. A no fuss solution! Convenient drop in ISO-CONV valve, No special tooling or machining necessary!This kit is a must for this transmission, not only does it shift quick, clean, smooth and nice, but it addresses the most serious complaints that have plagued this unit over the years. With this kit durability and dependability are greatly increased, plus you or your customer will love the way it works.For Performance and Heavy Duty vehicles use the 4L60E-HD2 Reprogramming Kit™. It has all the benefits of the SK 4L60E kit plus options for firmer shifts and our exclusive Gear Command feature.