I recently pulled my 2007 Western Star out of its regular servicing. (Just oil change etc...). The weather had been about minus 40, and had a chance to thaw out during the servicing.
Upon getting into my truck, I noticed that my diff lock light was on.
But it appears to disengage and engage when I need to. No signs of scrubbing on my tires - at least what I can make out.
Im thinking its a sensor. Or electrical. I checked my airlines, even dumped the air in my trailers to see if there was moisture. Nope. Nothing.
Im going to be dropping my trailers to see if I can get into a tire shop so they can lift the back end of my truck to make sure that they are disengaged.
Any other suggestions?