Check weathertech.com to see if they have a style that suits you. American made and heavy duty. Don't know if they list E450, but mats are the same as for any Econoline.
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RamblerGuy
2011 Sunseeker 3100
2016 Ford Edge Toad
I ordered these on Amazon. I got a message saying they would not fit our E450 but they do! Cheap enough too! I only needed the front mats and these worked well for my needs.
Does that mean they will fit any class c e450? We have the Forester 3171 and looking for a set of matts . I've read that some after market matts tend to slide on the already vinyl floors in the e450.
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1968 tent trailer
1985 Jamboree 23 ft
1997 Minnie Winnie 25 Ft
2016 Forester 3171DS (ordered March & arrived June 2015)
I have the weather tech floor mats. I had a 2013 3170 and traded in on a 2015 3010 and they fit the same. Website may not list 2015, but I don't think a whole lot has changed.
E450 year goes back aways at least 13 -14-15 all the same maybe 16 yes the mats will slide a little but not enough to cause a problem just adjust occasionly