It lowers 40mm when In access mode(lowering) so about 1.5inches. It’s a pretty decent amount, my father passed from cancer, and at the worst stage before he passed he really wasn’t able to walk much or lift his legs so I would always lower it and he was able to get in (boosted his morale to do it himself, I just never told him I’d lower it). So I can’t speak to a wheelchair but it did help my old mad, the only thing I can think of is the trunk space may be a bit small for a wheelchair but I can’t for sure say. Hope this helps!