GM trucks have hour meters in the odometer, trip odometer readout. My diesel has about 7500 hours/165K miles. I drove one of my other trucks today and the hour meter read 10.2 despite the truck being a 2005 w/38K miles. The meter went up throughout the day but I have no idea how/why it reset.

Has anyone else had that experience?

There is not a way to reset the hour meter in these trucks. For some unknown reason they sometimes reset due to a cluster malfunction.

One ratio that we use at ford and GM is 1 hr of idle time is usually = to 33 miles. So your truck with 38k should have been around 1200 hrs. Im guessing your diesel idles a ton for the amount of hrs you have on it

It does get real hot in FL in the summer......if I can see the truck it doesn't get shut off! But in reality it probably is tons of in town driving as well. I regularly can go through a whole tank of fuel without driving on the interstate once.

Thanks for the response...... Since you sound like a GM tech or at least a guy in the know....Any idea what the rattle is under the dash is on the left corner/side? Sounds like something (like a harness) slaps the underside of the dash on bumps. I have had 7 of these trucks (currently have 4) and have never heard this rattle or had the hour meter reset. Truck is a stripper 05 5.3, automatic bench seat rubber floor special!

If you have had the cluster replaced they could have programmed the miles and forgot about the hours also.

I've heard they'll sometimes get reset if you disconnect the positive battery cable and touch it to the neg. terminal while still connected to battery. Don't know how true it is though.

Mine kept resetting due to a bad battery, replaced the batteries and havent had a problem since

no, truck has never been back to dealer for anything. I just drove it myself this week and noticed the reset (which happened last week by my guesstimate).

that could be, battery is original but hasn't ever "not started."