Thanks. The compressor runs a lot. I do not understand the logic of the system, as it will pump up the front end whenever I stop at a light, etc. Which means that the system is lowering the front end while driving...why? Lately, the check light has been coming on sooner: used to be 50 minutes, now 20. It still pumps up and down, though. I have yet to see the system leak down anywhere. I am curious to know if I turn off the system (emergency shut off) if it locks it out so that the system does not work. I think it is just BS, since if there is a leak somewhere then shutting it off won't do anything. I would remove the system except the truck is 10 years old and has other issues.