Shortly after purchasing our rig we noticed the same thing. I don't know why they could not be attached an inch or 2 higher but the bigger the slide the more apt it is to sag and hold water.
We checked with Jayco thru our dealer and they said to bring the slide in about 6 inches and let it drain off. Then run it back out.
This has worked for us for years. Sometimes we go up on the roof with a long handled broom and sweep them.
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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