One problem related to differential unit has been reported for the 2003 Lincoln LS. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Lincoln LS based on all problems reported for the 2003 LS.
Repeated failure of left rear wheel bearing and left differential seal. Dealership has replaced wheel bearing and seal 2x, second time replaced left axle shaft also. First indication of problem is odor of gear oil leaking from differential, particularly after highway driving. Noticed it again today, (3/15/08) will be returning to dealer ASAP.