After lifting my 03 truck, I also ran into major clearance issues with my 5th wh toybox. I ended up using the dexter axle kit to place tandem leaf springs on top of trailer axles rather than underneath...This caused another slew of new issues, my stabilizers/jacks would no longer reach the ground without blocks, the steps into the coach required an additional stretch of groin muscles...and now the loading ramp is also steeper. What a pain!not a happy camper now having to adjust camper springs on 1999 Jayco Designer 3410. . Not liking my new ride at this time.