Hey all, I have a 1992 GMC sierra 2500, 5.7 liter automatic, with 4WD engaged by a lever and 110,000 miles. About 90% of the time, the truck will not go into 4wd drive, hi or low. It worked all last year, and this winter it started doing this. When it engages, it works normally, but getting it to engage is the issue. The indicator light works because when the 4wd works, the light is on, but when the 4wd doesn't engage, the light is off, as it should. Any ideas on a possible solution? Thanks, Brett