I picked up a 83 s10 blazer 4x4 with the 2.8v6 and 700r4 auto transmission with 108,120 miles on it. Today I had the coolant hose from the water pump to the heater block blow off and empty 3/4 of the coolent on the road. I installed an after temp,oil and voltage gauges, and thankfull the temp gauge didnt go past 190f. After letting it cool down and refilling the radiator and fixing the hose, I noticed the on the 4x4 selector, that the front diff is light up but the shifter is in 2wd and the light next to it comes on. After getting off work, I saw the front diff light was still on, but after stoping to drop off some thing, I came back to the car and the light was off. It stayed.off for a while but then light came back on. Im wondering if its in 4wd, even if the shifter is in 2wd with the light on or is it the sensor on the front diff perhaps not working because it got hosed with hot coolent and it is still running in 2wd mode. Also is there any way to know if its running in 4wd vs 2wd, other then jacking it up? I need to know because I dont want to cause the front diff to grenade on me.because of being driven on pavement, when it should not have been. Also before this I had no problem being in netural and shifting the.4x4 selector from 2wd to 4wd hi to netural 4wd low. Now its hard to go from 4wd high to netural to 4wd low and back and it makes a grinding.noise when going into netural from 4wd hi. Sounds like a manual trans grinding lightly. Does any one have any ideas? I also havent changed the transfer case fluid yet, I which I wonder if that might help.