If you do some research on the height of the new tire/rim combo vs the specs on the ones you currently have you should be able to determine if you have clearance.
I would like the largest rim and highest load range tire I could get in the space available. What you got from Jayco is the standard legal dept. answer.
Even a tire dealer, unless you have a great relationship would not want the liability of giving bad advice.
There is plenty of it free on the internet!
2011 351RLTS Eagle, Mor/Ryde suspension & pin box
06 F350 Lariat PSD, SRW, LB, CC, EGR delete kit, 16K DrawTite hitch, Timbrens, TST TPMS
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