Any folks out their having any hissing sounds right after using their ac, engine turned off.

Had my 2nd oil change @8200 miles. Ford service guy says shudder at start and hissing noise is normal.


FX4,3.73, SC, w/all the bells and whistle...

 

The hissing noise is normal. It is the pressueres in the system equalizing through the fixed orifice tube. The high pressure bleeds back through the orifice to the low pressure side creating a hiss or whistling sound. I have a 4x2 and havent noticed any shudder. There is a TSB 04-1-6
Some 1998-2004 F-150 4X4 vehicles with a one piece drive shaft may exhibit a clunking or grunting noise and/or a shudder sensation from the driveline. The condition will typically occur during light to moderate acceleration from a stop and/or braking. This may be caused by the slip yoke not sliding smoothly on the transfer case output shaft splines.
You need to lube the splines with teflon grease part#
D2AZ-19590-A I hope this helps.