Kevin Hart Will Require Weeks of Rehab After Car Crash

Kevin Hart is on the mend, but he won't be out of the woods for a long time, the comedian will require extensive physical therapy ... TMZ has learned.

Sources close to Kevin tell us he's expected to be released from the hospital by the end of the week. However, he'll have a heavy physical therapy workload in the coming weeks, along with a steady schedule of follow-up doctors appointments.

While we've been told Kevin's Sunday night back surgery was a success -- there's still work to be done to ensure he comes back 100 percent.

TMZ broke the story ... cops say Kevin was riding shotgun in his 1970 Plymouth Barracuda early Sunday morning when it careened off Mulholland Highway, leaving the driver and a backseat passenger pinned. Kevin left the scene to get medical help and was taken to a nearby hospital.

Crash investigators told us alcohol was not a factor, but we are told cops are looking into excessive speed as a possible cause of the wreck. A witness within earshot of the crash said they heard tires screeching -- like the vehicle was peeling out -- before hearing a loud boom.