Should ya be able to turn the fan on engine by hand when truck is cold? It won't turn freely & it runs all the time & makes lots of noise.
My fan is air activated and I have a switch on the dash that I can turn it on and off with (previous owner installed that). When the engine is off I can turn the fan by hand freely with no play as long as there is no air to it.
I have a 98 3126 and its been ok. To me it runs way too hotfor my liking.....I'm thinking about putting a 4 row radiator in it to see if that helps. Other than that....with decent maintenance its never really given me too many issues. Mine has around 350,000 miles (reman).
I do think its better at lower speeds seems to me to fall a little flat at highway speeds. I run right around 70mph with 3.73 rears and a 10 speed direct.
If the fan clutch is bad and the fan runs a lot - would that be a big drain on the engine ? I guess what I am really asking is would you notice a loss of power from the engine ?