Elon Musk tweeted a lot about the Tesla Model 3

A tweet-happy Elon Musk is giving out a lot of info about the Model 3

Elon Musk tweeted prolifically about the upcoming Model 3 sedan Friday morning.

The Tesla CEO jumped on Twitter to provide some information about the Model 3, the approaching Autopilot update and the tunnel-digging machinery scheduled for delivery.

First, Musk made it clear that the Model 3 will be a lower-priced version of its higher-end cars, not an improved model meant to replace or cannibalize them, as Musk said some people seem to be suggesting. The car is supposed to begin initial production in July and volume production in September.

Also, there is a next-gen Tesla Roadster on the way (the original Roadster was Tesla's first model), along with the Model Y "in a few years."

Early versions of the Model 3 will be rear-wheel drive only, just like the early versions of the Model S, Tesla's high-end sedan. He did indicate that there will be a dual-motor version of the sedan though, as well as a performance version.

Also, a digging machine is supposed to arrive in April to begin working on a tunnel. Musk has already started a digging project at SpaceX headquarters in Hawthorne, California, in the hope of finding a solution to Los Angeles' traffic problem.

Here are the highlights: