RE4RO1A Kit Shift Correction Package This valve body kit deals with these problems:* 2-4 band burn-up* Soft shifts* 1-2 accumulator seal blow-out* Inadequate lube oil (planet failure)* Poor line pressure* 4-3/3-4 shuttle problems* Regular and heavy duty options. This Shift Correction Package will eliminate erratic shifting characteristics of the unit after a rebuild.This kit delivers a better lube circuit which is needed to keep this unit on the road. Offers both regular and heavy duty options. Feel the noticeable difference in applications set up for heavy duty in pick-ups and Pathfinders. Note to purchasing: Ask for Superior part number KRE4RO1A