05 Quest Underbody Coating

Have a new 05 Quest with about 6000 kms on it and the exterior underbody coating has fallen off. Yes fallen off -peeled just like old paint. Anyone else have this problem? The spray on liner was a semi soft rubber compound and helped to deaden road noise. Van is very noisy now with the bare wheel wheels especially in the rain. Nissan has offered to pay for a rust proofing but have no answers for the noise level. Any suggestions?
Thanks