I have a '97 F250 Lariat Xcab 4x4 with the factory installed auto leveling air suspension. Occasionally, you can hear a buzzing sound like an compressor for about 5-10 seconds after shutting down the truck. I had assumed that this was always the auto level kicking in.

Lately, I've noticed that after several minutes (and once over an hour later) you can hear it kick in.

Is this normal? Have others heard this? What actually triggers the action? Just wondering if I'm starting to have some sensor problem causing it to kick in.

 

theHedge,

I as well have the load leveling suspension in my F250 LD and indeed, it does the same thing. The compressor is located close to your battery and it kicks on when the spring compression sensor activates it. This sensor is located very close to your air bag style load levelors mounted to your leaf springs. When a deflection is registered in the sensor due to load or a change in the spring position the compressor is engaged to fill the air bags until a nuetral spring position is obtained. This neutral spring position can be adjusted at the sensor. Since the whole system is pnuematic in nature some air leakage does occur over time and the sensor will start the compressor to recover the neutral position (this is normal). If you wish to you can disable the suspension with the switch located by the passenger kick panel.

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1998 RED F250-LD EC 4X4 Lariat, 5.4L, 3.73LS, 4WL ABS,
LOAD LVL SUS, TOWING PKG, SUPER COOLING PKG, 6 CD
CHANGER. GREY LEATHER INTERIOR.

MODS: PACESETTER TFX CAT BACK EXHAUST
AIRAID INTAKE SYSTEM
SUPERCHIP FLIP CHIP
MAG-HYTEC DIFFERENTIAL COVER
NAPA CERAMIC BRAKE PADS
BFG ALL/TA KO LT26575R16
FORD MOLDED MUD GUARDS
DURALINER W/ BULL RING TIE DOWNS
MAX SUPER WHITE HEADLIGHT & FOG BULBS
DASHMAT DASH COVER

FUTURE MODS: JBA HEADERS
STULL BILLET GRILLS
MAGNACHARGER BLOWER