MD80 CREW HAD A R MAIN GEAR RED LIGHT; SHOWING THE GEAR WAS NOT RETRACTED.

Narrative

INFLT DIVERSION; MECHANICAL. DEPARTING FLL; SAW RED GEAR LIGHT FOR R MAIN GEAR AFTER GEAR RETRACTED. LEVELED AT 4000 FT VICINITY OF FLL TO COMPLETE ABNORMALS. WITH NO AMBER GEAR DOOR LIGHT AND NO BUFFETING; DETERMINED THAT UNDERCARRIAGE WAS FLUSH. PROCEEDED ON COURSE TO DFW; CONTACTED DISPATCH TO SEE IF NEW IMPOSED AIRSPD CONSTRAINT OF 0.7 MACH COULD BE SAFELY FLOWN TO DFW. DISPATCH SENT RE-COMPUTED STEP-CLBS OF FL240; FL280; AND FL310; ARRIVING AT DFW WITH 5600 LBS. A LITTLE BELOW MY PERSONAL MINIMUMS; BUT LEGAL. LATER; COMPARING THE REVISED FUEL BURN WITH OUR ACTUAL; I REALIZED THAT WE HAD BURNED A LOT OF FUEL AT LOW ALT COMPLETING THE ABNORMALS WITH LITTLE PROGRESS MADE TOWARD DFW. WOULD NOW LAND WITH 3700 LBS -- BELOW MY LEGAL RESERVE. RADIOED DISPATCH; TOLD THEM I NEEDED A RE-FUEL STOP. WE AGREED ON MSY; AND I INFORMED DISPATCH THAT I AM OBLIGATED TO MAKE AN ENTRY DETAILING THE MECHANICAL AND MSY WOULD HAVE TO DEAL WITH THE WRITE-UP. ASKED THEM TO CONTACT THE MAINT CTLR ON THIS. PROCEEDING TO MSY; THEN 10 MINS LATER GOT AN ELECTRONIC MESSAGE. MSY HAS NO MAINT; WE WOULD BE GNDED AFTER ARRIVING MSY; SO BEST CHOICE WAS TO DIVERT TO MIA AND POSSIBLY CHANGE EQUIP. RETURNED TO BASE TO MIA; CHANGED EQUIP; THEN FLEW HOME.