I have a 99' Ford Expedition and whenever I drive about 20 minutes the 'check suspension' light comes on. Any ideas on what might be wrong or what I need to do?

This has the automatic load leveling system - right?? There would be a switch to shut it off when servicing the vehicle so it doesn't try to adjust while hoisted and that could have been left off and would tell you.

These also use sensors that are mechanical to an electric device to sense the load or height and will lift or lower as needed. These can break or be corroded and a quick look may find something wrong like that. The rubber boots of suspension that allow for lift can leak and hence not be able to adjust and would set a light off.

Just take a look at the items involved for now and check that the override switch is "ON" and system enabled,

T
Tom Greenleaf - MetroWest Boston - USA
http://www.acsource.com/

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