route between vlans with snat

We want to setup vlan4 , 5 , 6 on the F5. But currently we have snats in vlan4 that are set up to provide a unique ip for outgoing traffic from each of our internal servers. If we setup vlan 5 and 6 we can no longer get to vlan 5 and 6. I've considered using a forwarding server but that will not give us a unique outside address ip coming from the internal server. Is it possible to route snated traffic to another vlan? Simple case be able to ping vlan 6 when your snats on vlan4? One of our cases is DNS in in vlan 6 but the snats in vlan 4. Another case is internal server needs to reach a database on vlan6. Thanks for any help.