Embarrassed to be unaware of Woodward's Hardware; even googled it see store front...having lived in the smackdab middle of Santa Ana for a time. All kinds of history there to be sure. Owned residence of early Postmaster Chilton 1883 [wouldn't if that name very slightly different!], and surrounded by all kinds historic residences.

Frank's link to rolling door hardware will benefit many HMT'ers; sizes, capacity, mounting specs...you know, comparison shopping and all. lol.
Funny thing, the internet. I'm sure Woodward's is a retailer, not manufacturer, judging by picture supplied. Usually a search limits itself with too specific wording. Apparently I kept clicking retail sources, as consumers we are accustomed to that. Most nicer looking than heavy duty; decorator vs serious use. Don't recall ANY with a 4400 lb rating! That approaches weights of good sized fire doors - inclined track, counterweights, fusible links and all.
Depending on what is sought, many items sort faster from the bottom up "manufacturers of......" for example instead of "rolling door tracks". Also a good idea to dump cookies regularly. Make sites work for what you want - not what needs sold off.

OK. Now how about gap that will result by cutting floor out and pouring a concrete ramp? Door now rides just above floor, around 30" above grade, inside foot thick wall directly next to sidewalk. Really want to preserve the oak door, but a 30" gap isn't very secure IYKWIM. Largest vehicle is 10 wheel 22' 54k flat bed.
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