One bad winter trip in Colorado changed my mind about extended intervals, but hear me out. Ran 90k on a cartridge once and the only issue was a sticky unloader valve that cost me a road call. That chalky sludge you saw probably would have been fine for another 10k honestly. The real scam is the shops pushing it every 5k like clockwork when most guys are running dry roads and clean filters. Youre telling me that little desiccant bag cant handle more than 5k miles of highway driving? My old Pete went 120k with the original and I just drained the tanks weekly. Guess it depends on your air usage and how much moisture youre really pulling in.

Take the extra $400 as a lesson in how these guys actually operate. The contract is just a piece of paper until the car is on the truck. I've seen it happen more times than not, and the only real leverage you have is a backup plan. Next time, call three brokers and don't pay a deposit until you've confirmed the driver's name and rig in writing.