Re: Toyota Sienna Side Steps Running boards
In general, and based upon my experience (YMMV), our Siennas are low enough to the ground that "running boards" are not truly necessary or all that functional. They are more of a "style" modification.
I had mine installed as a "port/dealer" accessory after I rcvd delivery of the van. Mine are the OEM "pod-style". There is also another OEM style that blends in with the body panels. Which style your dealer supplies may vary. The "pod-style" is also commonly seen on other vehicles. For mine, the installation entailed temporarily removing the spare tire in order to drill a hole for a bracket (spare replaced to the same location afterwards) ...other holes for other brackets also had to be drilled. I did not DIY, it was a dealer outsourced job.
The floor of the van is relatively low already, so with running boards installed, your ground clearance is even further restricted. The running boards become CURB SLAPPERS / SCRAPERS (I have the scars to prove it). You've been warned. Also, there isn't enough depth to the boards to allow you a truly secure foothold. They are also slippery when wet. I had to install some of that traction-tape stuff. Realistically, neither grandma nor my 3-yr old use them because the floor is already easily reachable at a comfortable step-level.
I would save the $$$$$.
2004 XLE Ltd FWD Phantom Grey Pearl/Stone // 140K miles
. Pod-Style Running Boards
. OEM Hood Deflector (wimpy-version)
. 'kmead/SeanY' Rear-Wiper Salute
. 'mungpat' DIY Cabin Air Filter $$$-Saver
. Michelin HydroEdge (ex-Yokohama TRZ) ... looking for replacements
. Costco/Kirkland #9 battery
. Longer front wipers
. Britax Frontier 90