I had to change the solenoids in my transmission but still had to drive it and wait for them to appear. Delivered the next day, I decided to give it a try. I was in the delivery business so the system ran for the next 8 hours without noticing much of a difference. The next morning, however, the car shifted into second gear much better and the transmission fluid darkened as the engine oil showed it was breaking down the corrosion and clots that could limit its performance. In short, I was surprised at how much it improved my old Monte Carlo, so with new gauges it should be great.