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Online      Join Today ~ It's Free  Fan clutch ?  Discussion in
'Chevy Suburban Forum (GMC Yukon XL)' started by L5wolvesf, Jan
30, 2013.    1. L5wolvesf      L5wolvesf New Member      Hi all,
Been having a problem with my '99 7.4 (big block) running too
cold, usually well below 180. This seems to cause the 'burb to
get worse mpg than it should. It was suggested I swap out the
t'stat to a 195, so I just did, no change. In talking to a
mechanic (pro) I know we noticed the air behind the fan was
cold, really cold. Then we noticed the fan was turning when it
should not be.      Anyone have similar experience? I want a bit
more input before I spend the $$ on the fan clutch.      Thank
you,   2. a.graham52      a.graham52 New Member      im assuming
you have a machanical fan clutch and not an electric one. the
machanical ones will turn when the engine is running reguardless
of how hot the engine is. does it sounds like a jet engine all
the time when