TIL a cheap infrared thermometer saved me from a bad diagnosis

For years, I just used my hand to check if a brake rotor was dragging or a wheel bearing was hot, figuring it was close enough. Last Tuesday, a customer came in with a 'pulling to the right' complaint, and my hand said both front rotors felt the same temp after a drive. I borrowed a coworker's $30 infrared gun and found the right side was actually 80 degrees hotter. That pinpointed a sticky caliper I would have missed. Anyone have a favorite brand for these, or another tool that changed your diagnostic game?

4 comments

4 Comments

sullivan.quinn2mo ago

Remember how kellyr20 said you'd hear it? My buddy didn't, and his hand test missed a caliper that was cooking a wheel bearing.

kim_mason552mo ago

Eighty degrees hotter and your hand couldn't tell the difference? That's wild, it really shows how bad our own senses can be for this stuff. I would have sworn I could feel that big of a gap. Makes you wonder what else we're missing by just going by feel. I'm definitely adding one of those guns to my buy list now.

kellyr202mo ago

Honestly, the hand test is usually fine for catching a real problem. If a caliper was that stuck, you'd probably hear it dragging or smell it before you needed a number. Seems like overkill for most shops.

keith1642d ago

And yeah @kellyr20, I used to think the same thing until I had a Ford van where the caliper was dragging so bad the rotor was glowing in the dark and I still couldn't hear it over the engine noise. Your hand can only tell you so much when your palms are already calloused and used to working around hot parts all day. I got a cheap one from Harbor Freight that does the job but the laser on it is like 2 inches off from where it's pointing, so maybe spend the extra ten bucks lol.