Hello tmivie,
When you say you took the dryer apart and cleaned out all the lint, did you also check the vent system all the way to the outside and at the end where the duct exits your house? If you are getting heat and limited or restrictive air flow, your drying time will be excessive.. There may be other problems such as the blower itself isn't functioning properly to move the air out.. Since your dryer is electric, you can detach the vent line from the dryed and turn it on.. feel the exhaust flow to make sure it is pretty robust then reattach the vent and check for about the same flow at the exit point of your duct system. Let me know if that solves your problem or not so we can look at other ideas..
Regards,
Rick