Leaf spring and differential issue

so, I bought a 2015 DCSB TRD 4x4 about two months ago. It has been having a few strange things going on since I bought it. I had just sold my '14 DCSB TRD non 4x4 and know what they drive and sound like. But, the new one makes a loud clicking noise when first started and a humming noise on the highway. i pulled my light weight travel trailer once, tongue weight about 330 and a camper shell of about 200. I noticed the bump stops had hit the frame so it has bottomed out.

Took it in for regular service the day before and left it overnight. They kept it all day. They have made calls into Toyota for help. The suspension issue and they said the differential. I am aware of the TSB for the leaf springs even though I have the 4 leaf spring pack.

Anyone have any ideas on either issue?

 

Two words, AIR BAGS. I tow a 17' travel trailer with my bed full of water jugs and generator and have AirLift air bags with four leaf springs and have no problems. Don

 

I bought the Ride Rites and was going to have them installed today. But, put them on hold until they figured out the factory issues.