The front lower control arm has two different bushings. The forward bushings are quite rugged and may be functionally fine even with a few surface cracks in the rubber. The aft bushings are not solid - they have vertical ligaments that do crack, although replacement usually occurs at 100K plus miles. The cracks may start after 20-30K miles, but will usually be inconsequential for much, much longer. Have the shop show you the bushings and use good judgement.

Clean the oil off the differential and observe before resealing the unit.