When the windshield is selected on the fan controls the idle speed increases. Is that normal? On a previous vehicle it did the same thing because there was a leaking vacuum line.

Defrost? On cars with A/C it is common to increase idle speed when the Air conditioning loads the engine. Some FWD cars also have idle speed increased to compensate for steering load also. Does it do it just a little bit? sounds normal.

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Now have GDE full torque eco tune and eco transmission tune. Used an 02 liberty trans computer for my new trans tune.

x2, normal A/C engagement, defrost also engages it.

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05 CRD: H.D.S2 stat,WW Ironrock trilink&LCA's, OX rear,ARB front, 4.10's, ARB bumper, Suncoast,OME 3.5, JBA UCA,rock rails, Moabs&265/75 Duratracs, GDE tunes ,FFD fan,ARP's, 2 micron fuel, new valves,sasquatch battery tray & grid heater, tensioner relocated
Mech fan, VH & AC delete

Ok thanks.
I spy with my little eye a thermo fan there mountainman, what switch did you use for it and did you notice much of a gain in cooling? What other mods have you done?