I am a fleet manager for my company and recently, the company's 2000 GMC cargo van started to have transmission problems. The van was slipping badly and would have either rough shifts or it wouldn't shift at all. It wouldn't go beyond 40 MPH so before taking apart the transmission for a second rebuild, I decided to give LUCAS TRANSMISSION FIX a try since I have always used your Oil Stabilizer and have been very impressed by the quality of these products. I had added 1.5 bottles of your product to the transmission since we have an extra capacity oil pan, At first it didn't seem to do much except to help it shift, it was still slipping and shifting hard but was better than before, HOWEVER AFTER 2 MORE WEEKS A MIRACLE HAPPENED! AFTER NORMAL DRIVING, THE TRANSMISSION PERFORMANCE IMPROVED SUBSTANTIALLY! The shifts were flawless and the transmission worked so smoothly that it felt like a new truck! The driver even asked if I replaced the transmission with a new one! All in all, you have made me a true believer of your products!