Finance: A major Tesla bull just downgraded the stock and shares are sliding (TSLA)

Morgan Stanley's Adam Jonas thinks that Tesla will struggle to deliver its Model 3 mass-market vehicle in 2017.

Shares of Tesla slid 3% on the markets' open on Monday, to $314 after a Friday close at $324.

Morgan Stanley's lead auto analyst Adam Jonas, a reliable Tesla bull, downgraded the stock from "overweight" to "equalweight" in a research note published Monday. He retained his target price at $305, however.

Jonas thinks that Tesla will struggle to deliver its Model 3 mass-market vehicle in 2017. The car is scheduled to launch in July, with a production ramp to follow.

Tesla expects to produce 5,000 Model 3's per week by the end of 2017, with that pace rising to 10,000 at some point in 2018.

Jonas thinks that only 2,000 vehicles will be delivered in 2017, while Tesla will sell jut 90,000 in 2018, figures that the analyst considers to be below investor expectations.

The $35,000 Model 3 is a critically important car for Tesla, as it transitions from selling all-electric luxury vehicles to pushing toward annual deliveries of 1 million by 2020.

Morgan Stanley's Adam Jonas thinks that Tesla will struggle to deliver its Model 3 mass-market vehicle in 2017. Read Full Story