It appears the Sienna seats are superior to Ford van seats . . . are these being installed by members as strictly passenger seats or also as front seats? It appears that they can swivel and have lifting leg rests? Also suitable for front seats as long as seats can swivel and face back of van so leg rests can be raised? Thank you for clarifying!
Yes they are comfortable and, in my opinion, a much nicer seat than the stock offering in the vans. Are they your only option for upgraded seating? No, just one of many options. I originally chose to put them in the back of my van because of the recliner action. It worked out great for us... many, many "no complaints" miles from passengers.
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I also chose to put them in the front, mostly because of my wife but partly to have a matching interior. I put the passenger side on a swivel, otherwise the reclining feature is pretty much useless. (on the driver side, the foot rest will be a door to a storage compartment...after a bunch of modifications of course).
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They are a quality seat, there's no doubt about that. They are pretty easy to install in the back and not terribly difficult but lots more work to install in the front. Not that I really set out to do it, but I do have a pretty intimate knowledge of these seats just by virtue of how much time I've spent getting mounts designed for my own van. There's also another member on here who has done a pretty sweet install (Sheep Shagger) and Ujoint has some installed in his van and customer vans. The informational thread I started has some more info in it too.
http://www.expeditionportal.com/forum/threads/114704-The-not-so-definitive-guide-to-Sienna-seats