Is it a requirement to change the Hydraulic hoses of the lifeboat every 5 years ?

The requirements are SOLAS. There are guidelines like IMO MSC.1 Circ. 1206 rev. 1, but there are not such details mentioned.

I think you are talking about the Hydraulic hose of the free fall lifeboat davit. It is not a requirement to change the Hydraulic hoses of the lifeboat Davit. MSC Circ 1206, Rev.1 gives the guidelines for conducting maintenance on lifeboats and it suggests to check the condition of Hydraulic hoses.

The change of Hydraulic hoses is however considered to be a best practice. A lot depends upon the hydraulic hoses. If you get leakage, you loose the secondary method of lowering lifeboat. Most of the companies has this as a 5 yearly job in the PMS even when there is no statutory requirement to change the hose.