It is because of it being a GM unit. I decided to go with a gm4l80e which is in another league when it comes to strength comapred to the 200 & 700. Not to mention it is an electronic unit so shift points/frimness as well as when it locks/unlocks is adjustable thru the controller. Plus I will be able to use a paddle shifter which I think is just alot cleaner than a floor shifter. But there was more than a few negative comments about it. If I remember right the unit that Kielser (sp?) uses for there auto od unit is the 4l60e, I think it fits without all the aurgery that I needed to have done and it is still all electronic.