Is your vehicle's automatic transmission giving you trouble? Shifting difficulties and hesitation in your automatic transmission may be caused by a bad AT speed sensor. There are two speed sensors that work with your transmission, an input sensor and an output sensor. If your vehicle is having problems changing gears, lurching, or hesitating, you may need a replacement AT speed sensor. More often than you might think, problems with your vehicle are caused by failure of one of your many small but important components, so before you start planning to replace your transmission, make sure the problem is not with your AT speed sensor. Your first step with any transmission problem should be to replace the transmission filter and fluid, and if this does not solve the problem, consider a replacement AT speed sensor. Replacing or rebuilding your transmission will cost hundreds of dollars, so make sure you have discounted the possibility of small parts like the AT speed sensor as the source of the problem. A replacement AT speed sensor is inexpensive and may just be the answer to all of your transmission woes. Having a good understanding of the way your vehicle works can save you quite a bit of money, time, and hassle when you are able to diagnose and repair many of the problems yourself. Gearhead hobbyists completely deserve wonderful customer assistance when considering reliable car parts from us. So of course we've created a round-the-clock service call center to support all your questions. Nobody likes to pay for shipping, so all parts come with completely free shipping for every order greater than $50. If you spot a lower price elsewhere, let us know - we always beat any legitimate auto part price.