Jesus never went down to hell (lower parts of the earth) to preach as scripture says He went to preach to the spirits in prison. When Jesus laid in the tomb for three days his body was dead, but His spirit was very much alive.
In 1 Peter 3:19 it says Jesus being put to death in the flesh, but quickened by the Spirit went and preached to the spirits in prison. The spirits in prison that Jesus went to preach to are those angels that are reserved in everlasting chains under darkness unto the judgment of the great day. Scripture does not say what Jesus preached to them, but some speculate that He was proclaiming to these fallen angels that Satan had no victory over His death. These angels are separate from the third Satan gathered with him as these angels bound in chains kept not their first estate, but left their own habitation, he hath reserved in everlasting chains under darkness unto the judgment of the great day, Jude 1:5-7.
Ephesians 4:8 Wherefore he saith, When he ascended up on high, he led captivity captive, and gave gifts unto men. 9 (Now that he ascended, what is it but that he also descended first into the lower parts of the earth? 10 He that descended is the same also that ascended up far above all heavens, that he might fill all things.)
He led captivity captive and gave gifts unto men means that those who were a slave to sin are now given the free gift of God's grace through Christ as being the fulfillment of the Temple sacrifices. The lower parts of the earth just means the grave being underground.
These angels that have been bound and chained in prison until the day of judgement, Jesus was making show of them openly, triumphing over them in it, Colossians 2:13-15. This means that those who come to Jesus their sin is blotted out having spoiled these angels (principalities and power) who caused men to sin and that they too will be judged and cast into the lake of fire reserved for Satan and his angels.
1 Peter 3:18 For Christ also hath once suffered for sins, the just for the unjust, that he might bring us to God, being put to death in the flesh, but quickened by the Spirit: 19 By which also he went and preached unto the spirits in prison; 20 Which sometime were disobedient, when once the longsuffering of God waited in the days of Noah, while the ark was a preparing, wherein few, that is, eight souls were saved by water.
Jude 1:5 I will therefore put you in remembrance, though ye once knew this, how that the Lord, having saved the people out of the land of Egypt, afterward destroyed them that believed not. 6 And the angels which kept not their first estate, but left their own habitation, he hath reserved in everlasting chains under darkness unto the judgment of the great day. 7 Even as Sodom and Gomorrha, and the cities about them in like manner, giving themselves over to fornication, and going after strange flesh, are set forth for an example, suffering the vengeance of eternal fire.
Colossians 2:13 And you, being dead in your sins and the uncircumcision of your flesh, hath he quickened together with him, having forgiven you all trespasses; 14 Blotting out the handwriting of ordinances that was against us, which was contrary to us, and took it out of the way, nailing it to his cross; 15 And having spoiled principalities and powers, he made a show of them openly, triumphing over them in it.