You should be able to find the bolt that was there. I would use the same type as original.
I had 2 bolts shear on my slide out and they were grade 8. I replaced them with the same type.
I have no reason to second guess why it was there in the first place.
2011 351RLTS Eagle, Mor/Ryde suspension & pin box
06 F350 Lariat PSD, SRW, LB, CC, EGR delete kit, 16K DrawTite hitch, Timbrens, TST TPMS
Can't find what you're looking on JOF? Try:Jayco Owners Forum Custom Google Search
"It's easier to fool people than to convince them that they have been fooled." - Mark Twain