Imagine this: You’re driving overnight and you’re in the middle of nowhere. Suddenly, your engine starts derating. You pull over and do a forced regen, hoping to solve the problem, but it doesn’t work. You’re stuck on the side of the road for the night until you can get a tow to a nearby shop in the morning. The tow is over $1,000 and the shop is charging you more than $200 an hour for diagnostic work. That’s not even factoring in how much you’ll pay for parts and labor and the time you’ll spend waiting around for the truck to get fixed.

Short of an accident, there are few things worse than driving down the road and seeing your check engine light turn on — or any other hazard light for that matter. There are thousands of things that could be wrong with your truck, just as there are hundreds of parts on your truck that keep it running. Is it going to be a minor fix? Or is it something that’s going to keep your truck in the shop and off the roads for days?