Just to be clear, are you load balancing LDAP servers or you are making LDAP/LDAPS requests to Active Directory servers?
With AD, you should not be load balancing domain controllers due to the stickiness nature. With 2008 there were GPOs introduced to improve client DC fail-over and fall-back for clients. This would be a good addition to SSSD in the future to use the new GPOs:
Location: Administrative Templates\System\Net Logon\DC Locator DNS Records\ Entry Name: Force Rediscovery Interval.
If it is only LDAP, you may want to provide more details regarding your LB setup, whether there is stickiness, etc. in your config.