Air Carrier First Officer reported while on final approach to MIA airport the EGPWS gave warnings regarding 'too low; gear.' The gear indicating lights showed 3 green down and locked lights; the 3 red gear disagree lights were also illuminated. After landing the indications returned to normal.

Narrative

After a normal flight and initial portion of the approach and configuration into MIA I asked for gear down and flaps 15 at about 1500 AFE and the CA (Captain) complied and at about 1200 AFE I asked for flaps 30 and the landing checklist. When the CA started to run the checklist we both noticed that in addition to the 3 green down and locked lights; the 3 red gear disagree lights were also illuminated. There was a very brief discussion about the fact we had 3 green lights on the forward panel as well as 3 green on the overhead panel; so we were sure that the gear was in fact down and safe but were both unsure as to why the gear disagree lights were on. Shortly after that we began to get and EGPWS warning 'Too low gear.' We again double checked that we had 6 green lights which we did; but the 3 red gear disagree lights remained illuminated. As the warning continued I asked the CA something to the effect of 'do you want me to go around;' to which he replied something to the effect of 'no; we know our gear is down and locked; land.' I felt uncomfortable; but did not voice any further objections and continued to land. The landing was normal and upon landing the gear disagree lights extinguished. The remainder of the flight was normal. A ELB entry was made and the CA contacted Maintenance.