There's 16 lube points on each running board hinge.
I'd use either White Lithium spray as specified by Ram, or one of my favorites is dry film PTFE spray lube. Use it on a ton of stuff, RV, etc.
Garage lube is PDMS (Silicone) suspended in mineral oil and other flash off carriers.
Both PDMS(Silcone) and PTFE (teflon suspended in silicone) sprays are light load, high slip lubricants. Both provide similar lubrication while having slight advantages and disadvantages to each other. Temperatures, washout, etc.
White Lithium is for higher working loads. Yes, the overspray is messy, and it will attract more dirt than either of the other 2, but it's what Ram and nearly every OEM recommends for all hinges.
I use Lithium on the door hinges and friction springs and PTFE on the steps (well, I did it only once). PTFE is recommended as the lube of choice for Schwintek gear driven RV slides (just the gear shaft) and I've found it works great on all kinds of sliding surfaces and low load hinges like RV baggage and entry doors. Works great to quiet those squeaky friction hinges they're putting on RV entry doors without reducing their effectiveness.
For God's sake, don't use (legacy) WD-40.