BMW is kicking things into high gear as they prepare for the global launch of the seventh-generation 3 Series. Codenamed 'G20', the all-new sports sedan was already teased by the Bavarian automaker last August being tested at the infamous Nurburgring. Now, the company is once again putting the 3 Series in a battery of grueling tests before giving it the seal of approval.

From the blistering heat of Death Valley, USA; to the unforgiving cold in Sweden, the G20 3 Series was able to keep the cabin cool and warm in both occasions. There was also no squeaks and creaks on the 3 Series despite being put in both hot and cold temperatures. But besides getting to test the climate control system, BMW also got to test how effective the G20's flaps, doors, hood, and trunklid kept dirt and dust at bay while in the desert. On the other hand, the automaker also got to test the car's Dynamic Stability Control (DSC), M Sport differential and xDrive all-wheel drive on the slippery ice and snow.

All-new BMW 3 Series is in its last phase of testing before launch

Optimizing the car's aerodynamics was also one of the key goals set by BMW. At the company's Aerodynamic Test Center in Munich, the G20 3 Series has a drag coefficient of 0.23, perhaps one of the nameplate's best figures yet. They were able to do this by channeling the air around the underbody and optimizing the spoiler lip at the rear.

Also listed on BMW's to-do list for the new G20 3 Series were plenty of road tests. Besides giving it a proper shakedown at Nurburgring last month, BMW also brought the new sports sedan at the Aschheim proving grounds in Munich, as well as at the company's test facility in Miramas in Southern France.

All-new BMW 3 Series is in its last phase of testing before launch

In Munich, the G20's driving dynamics was honed undisturbed from prying eyes and from public roads. Meanwhile, in Miramas, BMW tested the G20's acceleration, steering and braking responses around handling courses and test tracks. It also underwent high-speed ring testing, slaloms and carved through twisty and spherical track testing.

BMW is still tight-lipped on what engines will be available on the all-new 3 Series. However, the Bavarian automaker did say that it will be available with the 'most powerful' four-cylinder gasoline-powered engine to be fitted in a BMW production car. Moreover, it will have better fuel economy and will be mated to an optimized eight-speed Steptronic automatic transmission.

All-new BMW 3 Series is in its last phase of testing before launch

BMW will likely hold the world debut of the all-new 3 Series at the 2018 Paris Motor Show this October.